1: Introduction to Modal Verbs
Modals are funny because they don’t act like normal English verbs.
1. They don’t need an auxiliary verb to make a question or a negative.
2. They don’t need an ‘s’ after he, she or it.
3. They are followed by the infinitive without ‘to’.
4. They mostly don’t change for tense.
5. We can usually only use one modal at a time (we can’t say I might could go).
Phrasal Modals
As well as the nine main modals (will / would / must / should / can / could / may / might and shall) we also have ‘phrasal modals’. These are expressions that are more than one word but that are used in a similar way to how we use modal verbs.
Examples are ‘have to’ and ‘be able to’.
Sometimes, phrasal modals are less formal than normal modals (‘be going to’ is less formal than ‘will’ and ‘have got to’
is less formal than ‘must’). However, this isn’t always true. ‘Be able to’ is more formal than ‘can’.
Most of the time, the phrasal modals don’t have exactly the same meaning and uses as the normal modal. Instead, the meaning is similar or related.
• Similar to ‘should’: had better, ought to, be supposed to
• Similar to ‘must’: have to, have got to,
• Similar to can/could: be able to / be allowed to
• Similar to may/might: be allowed to
• Similar to will/would: be going to, used to
Unlike normal modals, phrasal modals often have normal tenses and they can also be used after a normal modal in the same sentence: I might be able to help you later. (NOT: I might can help you later.) They can also be used together: I’m going to be able to help you later.
Need and dare, in slightly old-fashioned UK English, can be used with modal grammar. In modern English, they are mostly used as normal verbs with normal grammar.
• Do you dare to jump? (Normal grammar – modern English)
• Dare you jump? (Modal grammar – old-fashioned UK English)
• Do you need to go? (Normal grammar – modern English)
• Need you go? (Modal grammar – old-fashioned UK English)
Modal meanings
We don’t usually use modal verbs to say things that are straightforward facts. Instead, we use them to show our opinion about how likely it is that something is true or to interact with another person in a polite way.
Grammar books often say that there are two main ways that we use modals in English:
1: We use the modal verbs to say how likely we think something is. We’re don’t have control over the thing – we’re just giving our opinion about whether or not it’s likely to be true. We use modals in this way, for example, when we’re talking about probability, logical necessity, possibility and prediction.
2: We use modal verbs with a social meaning when we’re talking to other people to talk about things like willingness, permission and obligation and advice. We often use modals in this way to ask another person for something, for example, or to be polite.
It’s not the case that some modal verbs are used for talking about how likely something is and some are for social uses.
All modals can be used for both meanings.
We can see the difference in an example like this:
I meet a friend in the shop. She has a basket full of vegetables. I say: You must eat a lot of vegetables!
(I feel quite certain that it’s true that she eats a lot of vegetables, because I see all the vegetables in her basket. This is a logical use of ‘must’ – I’m using ‘must’ to show that I’m certain).
My husband is feeling tired. He’s only eaten chips and burgers for a week. I say: You must eat a lot of vegetables! Then you’ll feel better. (I’m giving my husband strong advice. He doesn’t eat enough vegetables and I’m saying very strongly that I advise him to eat lots. This is a social use of ‘must’ to give advice or say something is necessary.)
The modals with perfect and continuous infinitives
We tend to use the continuous infinitive (be + verb-ing) most with ‘will’ and modals of obligation, possibility and logical necessity. The continuous infinitive is not usually used for volition or ability or permission.
We often use the perfect and continuous infinitives for probability and logical necessity.
• Amanda might have missed the bus.
• Julie can’t be working now – it’s 10pm!
We use the perfect and continuous infinitives for obligation (they generally suggest that the thing is not happening / didn’t happen).
• I ought to be studying now.
• She should have finished the report last week!
It’s possible also to use the perfect continuous infinitive.
• You should have been studying when I called you.
In the same way that we use ‘will’ with the continuous infinitive (will + be + verb-ing) to talk about the future as a matter of course, and remove the ambiguity of the volitional meaning of will, we can also use the continuous infinitive with other modal verbs that talk about the future.
• He might be leaving this afternoon. (‘He might leave’ suggests that he might choose to leave, rather than it’s already arranged for him to leave.)
Passive / perfect / continuous infinitives
We can use the passive infinitive (be + past participle) after modal verbs.
• The report might be written by Julie.
• The train must be delayed by the weather.
We can also use the perfect passive infinitive (have + been + past participle)
• The children shouldn’t have been taught by that teacher. The bread must have been bought by mum.
Past modals
Traditionally, some grammar books split modals into past and non-past and list ‘could, would, should and might’ as the past modals. However, this difference is a bit more complicated than it looks.
It’s true that we use ‘could’ as the past of ‘can’ when we’re talking about ability, permission and possibility.
• I can play tennis.
• I could play tennis when I was six.
• John said that he could play tennis.
It’s also true that we use ‘would’ as the past of ‘will’ for prediction, characteristic behaviour and willingness.
• Lucy won’t come with us.
• Lucy wouldn’t come with us.
• Amy said that Lucy wouldn’t go with her.
There is also a very old-fashioned use of ‘might’ as the past of ‘may’ for permission. This is very rare now. It’s still possible to use ‘might’ instead of ‘may’ in reported and indirect speech.
We don’t really use ‘should’ as the past of ‘shall’ any more. It’s more useful to think about them as having completely separate meanings.
In many situations, we prefer to use a semi modal like ‘be going to’ or ‘have to’ if we want to talk about the past. It’s also true that sometimes we use a perfect infinitive to express tense with modal verbs. You can read about this in each section.
• You must be cold (present).
• You must have been cold (past).
However, there are three situations where we use the ‘past’ modals in the same way as we use the past tenses of normal verbs.
1: Hypothetical situations
We use these ‘past tense modals’ to talk about things that are hypothetical. This means that they aren’t really true. This is the same as the way that we use the past tense of normal verbs when we’re talking about something hypothetical or imaginary.
• If I could, I’d go to the beach now.
• I would come and help you, but I’m really busy today.
We also use ‘could’, ‘would’, ‘should’ and ‘might’ in unreal conditionals. You can learn more about this in the conditional course.
Notice that in a subordinate clause, we don’t tend to repeat the modal.
• In that situation, I would work until I finished the project. (Not: until I would finish)
We can use ‘past’ modal + have + past participle for things that weren’t true in the past. This is using a kind of ‘double past’ to talk about unreal things in the past. With normal verbs, we usually use the past perfect, which is also ‘double past’ for unreal things in the past.
• I could have studied medicine but I decided not to.
• I would have gone home earlier but John really wanted me to stay.
2: When we want to be polite or tentative
Just like we use the past tenses of normal verbs to make a request more polite, we also choose these past modals (especially could and would) when we want to be polite or tentative.
• Could I borrow your car?
• Would you help me later?
We used to use ‘might’ as a more tentative or polite form of ‘may, but the difference between ‘may’ and ‘might’ is disappearing. A few people still feel that might is more tentative than may, but this feeling is becoming less and less common.
We also use these past modals to give our opinion in a more indirect or tentative way.
• I think the report could be improved.
This includes using ‘would/wouldn’t’ to show disagreement in a polite way.
• I wouldn’t say that.
3: Indirect and Reported Speech
In indirect and reported speech when we decide to backshift, will becomes would and can becomes could. May often becomes might.
• Direct speech: I can speak Polish.
• Indirect speech: Lucy said that she could speak Polish.
• Direct speech: John will help us later.
• Reported speech: Lucy said that John would help us later.
• Direct speech: The train may arrive late.
• Reported speech: Lucy said that the train might arrive late.
2: Modals of Permission
Asking for permission
It’s normal to use ‘can’ and ‘could’ to ask for permission. ‘Could’ is more polite and it very commonly used between adults.
• Can I sit here?
• Could I sit here?
‘May’ is mostly used between children and parents or teachers. When it’s used between adults, it’s quite formal.
• May I sit here?
‘Might’ is now very formal and old fashioned. It’s rare to hear it.
• Might I sit here?
‘Be allowed to’ is mostly used between children and adults. If it’s used between adults it’s often asking about an outside rule.
• Am I allowed to sit here?
It’s possible to use can’t and ‘couldn’t as negative questions. Normally here we mean ‘isn’t it allowed?’ – we are asking the same thing as the normal question, but we are expressing surprise.
• Can’t I sit here?
• Couldn’t I sit here?
However, if we use ‘not’ separately and stress it, it’s possible to ask for permission not to do something.
• Can I NOT do the report? = is it okay if I don’t do the report?
• Could we NOT meet tonight? I’m really tired.
Future permission
It’s possible to use ‘can’ or ‘could’ with a future time word to ask for future permission.
• Could I borrow your car tomorrow?
• Can we leave at six?
We can also use ‘will be allowed to’. This stresses that the person isn’t asking permission now but for later.
• Will I be allowed to leave early?
Giving and Refusing Permission
We don’t usually use ‘could / couldn’t’ in the reply when someone asks for permission.
• Could I sit here? Yes, you can / no you can’t. (NOT: yes you could / no you couldn’t)
Exception: we can use could in the answer when we are talking about something hypothetical.
• Could I hand in my essay next week?
• Well you could, but then I won’t really have time to mark it properly.
It’s also possible to use ‘must not / mustn’t’ to tell someone that it’s not allowed to do something. See the section about obligation for more about this.
• You mustn’t sit there!
• You mustn’t come home late.
Normally, we use ‘can’t’ to say that something isn’t allowed. But (in the same way as with negative questions) we sometimes use ‘can … NOT’ (the stress on ‘not’) to say that it’s okay not to do something.
• You can come to the party or you can not come to the party, whatever you like.
Talking about rules and laws in the present / future
We usually use ‘can / can’t’, ‘be allowed to’ and ‘must not’ to talk about rules or laws.
• You can’t travel on the bus without a ticket. Everyone can park by the station.
• You’re not allowed to smoke in the theatre.
• You mustn’t park next to the entrance.
More formally, we can use ‘may / may not’ in the same situations, but this is not common.
• Everyone may park by the station.
We also use ‘can / can’t’ and ‘be allowed to’ to talk about permission that has already been given or refused.
• I’m not allowed to go to the party tonight.
• The children can watch TV after dinner.
Talking about rules and laws in the past
To talk about general permission in the past, we use ‘could / couldn’t’ and ‘was / were (not) allowed to’.
• When I was at school, we could go to the gym at lunchtime.
• When I was a child, I couldn’t watch TV in the morning.
However, we don’t use ‘could’ to talk about one particular instance of permission in the past. Instead, we need to use
‘was / were allowed to’.
• Last night, she was allowed to go to the party.
• Not: last night, she could go to the party.
It’s okay to use both ‘couldn’t’ and ‘wasn’t / weren’t allowed to’ for one particular instance though.
• Last night she couldn’t go to the party.
• Last night she wasn’t allowed to go to the party.
Hypothetical / conditional permission in the present / future Could = would be allowed to
This is used to talk about permission when we want to use a hypothetical or conditional meaning.
• He could come late. Nobody would mind (= he would be allowed to come late).
• You could stay at home but then I wouldn’t be able to do all the work.
• If John came early to help, Lucy could arrive whenever she liked.
Hypothetical / conditional permission in the past
We use ‘could + have + past participle’ to talk about permission for things that didn’t happen in the past. This is used for conditional and hypothetical situations.
• Could I have gone home early? (I didn’t go home early but I’m asking if it was allowed.)
• Could we have delayed the meeting? (We didn’t delay the meeting but I want to know if it would have been possible.)
We can use could + have + pp in this way to talk about something that would definitely have been allowed in the past, but that didn’t happen.
• I don’t know why he decided not to come at all. He could have come late.
We also use will/shall for rules e.g. of exams and competitions
• The judge’s decision shall be final.
Permission or possibility?
Sometimes it’s really hard to know if a sentence with can is about permission or possibility. Often in this situation, it can be both and we have to use the context to decide.
• Can Julie come to the party? (= is Julie allowed to come to the party? Or ‘is it possible for Julie to come to the party?)
3: Modals of Obligation and Advice
Present obligation and prohibition
Obligation is when someone tells you to do something or gives you an order to do something. We can also tell ourselves to do something. We can use must / must not and have to for very strong obligations, like a law and also for weaker obligations like telling someone to do something.
• You mustn’t use your phone when you’re driving. (It’s the law.)
• You must stop smoking. (=I’m telling you to stop smoking.)
• I must go home and study. (I’m giving myself an instruction or order here.)
We can also use ‘have to’ or ‘have got to’, with almost the same meaning.
• You’ve got to stop smoking.
• I have to go home and study.
‘Must’ and ‘have (got) to’ can also be used in non-personal warnings and rules that are based on outside facts, rather than human ideas.
• The machine must be unplugged before cleaning.
• The machine has to be unplugged before cleaning.
Prohibition = it’s not allowed
Can (permission) and must (obligation) have very different meanings in the affirmative. But they are quite similar in the negative, when they tell someone not to do something. In fact, US English often uses ‘can’t’ in the same situation that UK English uses ‘mustn’t’.
• You mustn’t smoke here.
• You can’t smoke here.
• You mustn’t go into the kitchen.
• You can’t go into the kitchen.
Sometimes we also use ‘may not’ or ‘be not allowed to’ in the same situation. See the section on permission for more about this.
There are a few small nuances of meaning here. ‘Mustn’t’ can suggest that it’s the speakers opinion, whereas ‘can’t and
‘be not allowed to’ often suggest that there is an outside rule. But we can also use
‘mustn’t’ if we want to say there’s some natural reason (not a human rule) why something isn’t a good idea.
• You mustn’t touch the oven!
Must and have to
Some English speakers feel that ‘have to’ or ‘have got to’ are talking about an outside authority (like a teacher or the rules). On the other hand, they say that when we use ‘must’, we are giving ourselves an internal obligation. However, not every English speaker thinks this and mostly we use ‘must’ and ‘have to / have got to’ interchangeably.
Speakers of US English are much more likely to choose ‘have to / have got to’ rather than ‘must’ in this situation.
Past obligation and prohibition
‘Must’ has no past tense (and we don’t use ‘must + have + past participle’ here – that’s only for logical necessity) so we use past of ‘have to’ when we are talking about the past.
• We have to / must wear a uniform now.
• We had to wear a uniform, when we were at school.
We can also use ‘couldn’t’ or ‘wasn’t / weren’t allowed to’ for prohibition in the past, for both general and specific situations.
• We couldn’t smoke at school.
Future obligation and prohibition
We can use ‘must’, ‘have (got) to’ or ‘will have to’ for future obligation. We tend to use ‘must’ or ‘have (got) to’ rather than ‘will have to’ if we’ve already made the arrangements.
• You’ll have to go to the dentist when we get back from holiday.
• I’ve got to go to the dentist later today.
• We will have to wear a uniform, when we start school in the autumn.
We use ‘won’t be allowed to’ or ‘can’t’ or ‘mustn’t’ for prohibition in the future.
• You won’t be allowed to eat during the film.
• You mustn’t eat during the film.
• You can’t eat during the film.
Absence of obligation or necessity Present: Don’t have to / haven’t got to
• You don’t have to get up early tomorrow.
Past: Didn’t have to / didn’t need to
• We didn’t have to go to bed early when we were children. Our parent let us go to bed whenever we liked.
• She didn’t need to get up early this morning.
Some speakers might use ‘needn’t have’ and in that case a few people feel that it has a different meaning from ‘didn’t need to’. However, using ‘needn’t have’ is quite old-fashioned and most people now use ‘didn’t need to’ for both meanings below.
• She didn’t need to bring her coat. (We don’t know if she brought it or not.)
• She needn’t have brought her coat. (She brought it, but it wasn’t necessary)
Future: We use won’t have to / won’t need to for lack of obligation in the future, as well as using ‘don’t have to’ and
‘don’t need to’.
• You won’t need to get up early tomorrow. Sleep as long as you like.
• You won’t have to get up early tomorrow. Sleep as long as you like.
• You don’t have to get up early tomorrow – it’s Sunday.
• They don’t need to come to the meeting.
Strong advice
We use ‘must’ for strong recommendations.
• You really must read this book!
• You must see the new film!
This can also be used for offers. (See the section on Volition for more about this.)
• You really must have some more cake!
Medium obligation and advice
‘Must’ can be too strong to say to someone directly. We often use ‘should’, which is has a more gentle feeling. ‘Should’
is used to say what the speaker thinks is a good idea or what the speaker thinks is morally right. It’s also used to talk about requirements that come from the outside.
‘Ought to’ is used in exactly the same way, though it is less common than should.
• You should go to the dentist.
• People shouldn’t drop litter.
• They ought to get a new car.
When we use ‘should’, it’s possible that the action won’t happen. This isn’t true with ‘must’.
• He should help Julie, but he won’t.
• NOT: he must help Julie but he won’t.
‘Should’ can also be used instead of ‘must’ to make orders or instructions sound more polite.
• The form should be filled in using black pen.
• The machine should be turned off before cleaning.
Past advice
We use ‘should(n’t) + have + past participle’ to talk about something in the past that the speaker thinks was a good idea but that the other person didn’t do. This form is hypothetical, because it’s imagining something that didn’t happen, and is often used to criticise people.
• You should have gone to bed earlier. (But you didn’t)
• You shouldn’t have quit your job. (But you did quit your job.)
We can use ‘ought(n’t) to + have + past participle’ in the same way.
• You ought to have arrived on time. (In fact, you were late.)
Be supposed to
We use ‘be supposed to’ to talk about an external rule or obligation. Often, it’s the case that the rule or obligation isn’t being followed or might not need to be followed.
• We’re supposed to arrive at nine. (It would be great if we arrived at nine. But we’re actually going to arrive at 9:30.)
• You’re supposed to be sleeping! Why are you here?
Using ‘would’ for advice
I would = I think you should. Often ‘if I were you’ is either added or implied.
I would study a bit harder. (= I think you should study a bit harder.) I would leave an extra hour for the journey.
Had better
‘Had better (not)’ gives advice about the best thing to do in a particular situation. It often has a sense of urgency and can be a warning or a threat.
Your dog had better not dig up my rose bushes again!
May / might as well
We can use might as well or may as well to talk about something that you think is the best idea in the situation, even if you don’t really want to do it. There isn’t a better idea or choice.
• The restaurant is closed. We may as well go home.
• I might as well get a job, now that my business has failed.
We can use ‘might + have + past participle’ for the same meaning in the past. In this case, you didn’t do the action – it means ‘it would have been the best thing’.
• The restaurant was closed. We might as well have gone home.
4: Modals of Volition
Volition means something like ‘when we choose to do something’ or ‘do something willingly, because we want to’. So requests are asking someone if they want to do something. And when we refuse we’re saying that we don’t want to do something.
Willingness and refusal (= I want to / I don’t want to)
Willingness = I am happy to do that or I want to do that. It’s most often used for things that we decide around the time of speaking rather than things we have already planned.
We use ‘will’ to talk about things we are (or someone else is) happy to do. Because ‘will’ also has a future meaning, the thing we are talking about is usually in the future.
• Will you help me tonight? (= Are you happy to help me tonight?)
• Yes, I will. (= Yes, I’m happy to help you / I want to help you.)
In the negative, we are refusing to do something.
• I won’t go! (= I refuse to go)
• She won’t eat her vegetables (= she refuses to eat her vegetables).
If we stress ‘will’ or ‘won’t’ this makes the volition part stronger.
• I WILL give up smoking! (= I am determined to give up smoking)
• I WON’T fail the exam again!
If we stress ‘will’ or ‘won’t’ when we are talking about other people, it suggests that they are stubborn.
• If you WILL smoke so much! Of course you have a sore throat!
We can use a modal ‘will’ in the if-clause in the first conditional, where normally we’d expect a present tense. We don’t do this if ‘will’ is being used just to predict the future, we only do this when ‘will’ has a ‘willingness’ meaning.
• If you’ll help me, I’ll be so happy (= if you want to help me).
• If you help me, I’ll be so happy (= normal first conditional).
Willingness in the past
We can use ‘would’ and wouldn’t for willingness and refusal in the past. Like with ‘could’ for permission or ability, we don’t use ‘would’ to talk about a single occasion of willingness in the past, but we can use it to talk about general willingness.
• NOT: Yesterday I asked Julie and she would come with me.
• Yesterday I asked Julie, but she wouldn’t come with me.
• In her last job, her secretary would answer the phone, but she wouldn’t make coffee.
For a single occasion, we use the past simple or another expression like ‘she was happy to’ or ‘she agreed to’.
Willingness for inanimate objects
We sometimes use ‘will’ to talk as if we’re giving an object feelings about what it wants to do!
• Will this door open?
• How high will that ladder reach?
• My car won’t start!
• My computer won’t turn on!
Requests
Of course, we don’t always want to talk about our own willingness or refusal. Sometimes we want to ask other people if they are happy to do something. We can also use ‘will’ to make requests and ask people to do things.
• Will you call me later please?
• Will you buy some milk on the way home?
However, because this is a request, we care about being polite, so it’s very common to use ‘would’ instead of will.
• Would you buy some milk on the way home?
We also often use ‘can’ and ‘could’ to ask people to do things. Again, ‘could’ is more polite and is much more common.
• Can you please pick up the children?
• Could you pass the salt?
It’s also possible to say:
• Would you mind getting some milk?
‘Can’ used in this way is sometimes ambiguous with the ability / possibility meaning of can. So, can you pick up the children might mean ‘please pick up the children’ or it might mean ‘are you able to pick up the children – is there enough time for you to get there after work?’. Often, it’s not really important which meaning we are using, but sometimes we might say something like:
• Can you get some milk?
• I could, but I won’t. It’s your turn.
We can also use ‘will you?’ as a question tag. This is much less polite.
• Make me a cup of tea, will you?
With negative questions, there are two possible meanings.
• Can’t you come early? (= Isn’t it possible for you to come early?)
• Can you not come early? (= Please don’t come early.)
• Won’t you go to the party? (= Don’t you want to go to the party?) Will you not go to the party? (= Please don’t go to the party.)
Orders and imperatives
Of course, we are not always totally polite when we ask people to do things for us. Sometimes we say things more strongly.
We use ‘will’ for orders. This often has a very, very strong, military feel. It’s almost like we’re telling another person what they want. It’s not a good idea to use this in normal life!
• You will do as I say!
We can use ‘shall’ in the same way. This is very strong and also very old-fashioned.
• You shall do as I say!
We also sometimes use ‘can’ to tell people more gently what to do.
• You can sit here. (= Sit here!)
We also use ‘must’ and ‘have (got) to’ to tell people what to do. You can learn more about this in the section on Obligation and Advice.
• You must arrive early.
• You have to leave now.
Offers
We use ‘can’ and ‘will’ and ‘could’ for offers.
• I can help you tomorrow.
• I’ll help you tomorrow.
• We could send you some information.
When we’re asking a question, we use ‘can’ and ‘could’ and ‘may’. It’s like we’re asking permission to do something nice for someone.
• Could I get you a coffee?
• Can I get you a coffee?
• May I get you a coffee?
We can use ‘will’ and ‘would’ to ask about willingness, but it’s really an offer.
• Will you have some cake?
• Will you have some cake?
• Won’t you have some cake?
We sometimes use ‘must’ to make offers. This is actually very polite.
• You must have some more cake!
We also use ‘must’ to make offers that are actually quite vague and might not happen.
• We must meet up for a coffee sometime.
We can use ‘shall I?’ or ‘shall we?’ to make offers in UK English
• Shall I carry your suitcase for you?
• Shall we come early and help you cook the food?
• Shall I bring you a cup of tea?
Making suggestions / talking about choices
We can use ‘shall we’ to make suggestions in UK English. It means ‘let’s’ or ‘how about’?
• Shall we go out for dinner tonight?
• Shall we book a flight later today?
• Shall we go to see Julie at the weekend?
It can be used as the tag question for ‘let’s’.
• Let’s meet up for coffee soon, shall we?
US English uses ‘should’ instead of ‘shall’ for suggestions.
• Should we go out for dinner tonight?
We can also use ‘might / can / could’ to make suggestions or talk about choices. ‘Might’ sounds more formal and old fashioned.
• You might ask John to lend you his car.
• You can leave early if you hate it.
• We could have Italian food tonight.
We also use ‘can’ and ‘could’ to make suggestions about what people should do.
• You could tidy the kitchen.
• Lucy can buy some milk.
We often use ‘can always’ and ‘could always’ here. Sometimes this is a more tentative suggestion.
• We could always just have dinner at home.
• You can always quit your job. (= it’s always an option to quit your job) She could always just come home if she hates it.
We can also use ‘would’ in suggestions if we want to be more tentative.
• It would be a good idea to get together.
Promises and threats
We also use ‘will’ for promises and threats (where a promise is the same as a threat but a promise is a good thing and a threat is a bad thing).
Promises
• I promise that I’ll arrive on time.
• My government will reduce unemployment.
Threats
• Throw that ball indoors one more time and I’ll put it away.
Intentions
An intention (something that’d we’ve already decided that we’re going to do) is most often expressed with ‘be going to’.
This isn’t always clear-cut, however.
• I’ll meet you at the café (= I promise to meet you there)
• I’m going to meet you at the café (=I’ve already arranged to meet you there)
We also use ‘be going to’ to make it clear that we’re asking about someone’s intentions, rather than making a request.
• Will you come tomorrow? (One possible meaning is ‘could you please come tomorrow?’)
• Are you going to come tomorrow? (= Have you already made a plan to come tomorrow? This is definitely not a request.)
Wishes and hopes
Wish + ‘would’ = a desire for another person (not) to do something.
• I wish you wouldn’t talk with your mouth full.
We can use ‘may’ in wishes and hopes.
• May you live a long and happy life!
• May the best team win!
More normally, we use ‘will’ with hopes.
• I hope that she’ll come to the party.
Tentative and hypothetical willingness or preference
We often use ‘would’ with verbs that talk about think we like or dislike or hate or prefer. These verbs are sometime called
‘verbs of preference’ and include ‘like / love / hate / prefer / dislike’. In this case, ‘would’ can have two meanings. It can be used to be polite / tentative, especially when talking about invitations. It can also be used to talk about things that are hypothetical or imaginary.
We often use ‘would + like / love’ to reply to an invitation politely. This is something we think we can really do, but we use ‘would’ for politeness.
• I’d love to come to your party!
Similarly, we use ‘would prefer’ to be polite.
• I’d prefer coffee, if you don’t mind.
On the other hand, sometimes we use ‘would’ with this kind of verb to talk about things that are hypothetical. That is, we don't think they are really going to happen.
• I’d love to travel round the world.
• I’d prefer to never get old.
• I’d hate to work for the government!
You can see the difference that adding ‘would’ makes in this example.
• I like to run every day (= I do this now and I enjoy it).
• I would like to run every day (= I don’t do this now but I wish that I did.)
We can use ‘would have + past participle’ of verbs of preference to talk about things that didn’t happen in the past.
• I would have liked to go to art school (but I studied law instead).
• I would have hated to grow up in a cold country! (I grew up in a warm country.)
In the past, people sometimes used ‘should’ instead of ‘would’. This is very, very rare in modern English.
• I should love a glass of lemonade (= modern English: I would love …).
I should have liked to go to art school, but it wasn’t possible (= modern English: I would have liked …)
5: Modals of Logical Necessity
We use modals of logical necessity when we decide that something is necessarily true or not true. It means something like
‘I’ve looked at the evidence and I think the only possibility is that this thing is true or not true. Or I’ve looked at the evidence and I think this is the only possible answer.
We use ‘must’ for affirmative sentences and ‘can’t’ for negatives and questions. So, in this case, the opposite of ‘must’ is
‘can’t’.
• She must be at home. (I think the only possible answer is that she’s at home.)
• She can’t be at work. (I think the only possible answer is that she is not at work.)
Compare these with ‘she is at home’, which is just a fact and doesn’t give us any idea about the speaker’s opinion. If we use ‘must’ or ‘can’t’, we show what the speaker thinks and this based on the speaker’s understanding of the evidence or the situation.
We can use ‘must’ and ‘can’t’ in this way to talk about single actions, states and continuing actions.
We might choose to use the continuous infinitive to talk about something that’s in progress at the moment of speaking.
• She must be working now.
We often use the continuous infinitive to avoid the ambiguity of the obligation meaning of ‘must’.
• Lucy must be staying at this hotel (it’s my opinion that she’s staying here).
• Lucy must stay at this hotel (I am telling Lucy that she is obliged to stay here).
We also often use ‘have to’ and ‘have got to’ with the same meaning here.
• She has to be at home.
• She’s got to be at home.
When we’re talking about the past, we can also use ‘had to’, with roughly the same meaning as ‘must have’ (we don’t use
‘has to have been’). However, we need to be careful, because ‘had to’ is more commonly used for past obligation (when I was at school, we had to wear a uniform). There isn’t a trick to know the difference – it’s just in the meaning of the sentence.
• She must have been at home.
• She had to be at home – I’d already tried her work and her usual café.
We can also use ‘does not have to’. This means something isn’t necessarily true.
• A: She must be at home.
• B: No, she doesn’t have to be at home. She could be at school.
Future
We often choose the continuous infinitive when we’re talking about the future with ‘must’, because that avoid the ambiguity of the meaning of ‘must’ for obligation.
• Lucy must come tonight (we can understand this as saying it’s necessary for her to come).
• Lucy must be coming tonight (otherwise she wouldn’t have asked David for a lift).
• Lucy can’t come tonight (we can understand this as saying that Lucy isn’t allowed to come).
• Lucy can’t be coming tonight (or she would have called us to arrange a time).
When we’re talking about future states, there is ambiguity that it’s more difficult to avoid.
• Lucy must be here tomorrow. (Usually we understand this as obligation)
Using ‘can’ and ‘mustn’t’
Mostly we use ‘can’t’ (only in the negative) to show that we think something is necessarily not true.
We don’t use ‘can’. However, there are a few cases where it is possible to use ‘can’.
We use it with negative adverbs like ‘hardly’.
• She can hardly be at home.
We can use it for questions (to mean isn’t it logically possible that?’ – note that this is different from asking if something is likely or probable)
• Can she be at home?
In a similar way, we can use ‘can have’ for past questions.
• Can she have been at home?
• She can hardly have been at home.
We can also use ‘can’ to contradict something.
• A: She can’t be at home.
• B: Yes, she can.
Similarly, we can use ‘mustn’t’ for logical necessity in tag questions.
• She must be at home, mustn’t she?
Couldn’t
We can also use ‘couldn’t’ in the same way as ‘can’t’. In the same way, we use ‘couldn’t have’ for the past and we use
‘could’ to ask about possibility in with negative adverbs and in questions. This is more common in US and Canada.
• She couldn’t be at home. (= it is not possible that she’s at home)
• She couldn’t have been at home.
Past
We use ‘must have + past participle’ and ‘can’t have + past participle’ to talk about things that we believe happened in the past.
• Why didn’t Julie come to meet us yesterday? She can’t have been at home.
• Why didn’t Julie come to meet us yesterday? She must have been at work.
We can use ‘must have been + verb-ing’ or ‘can’t have been + verb-ing’ to talk about something that we think was in progress in the past.
• Why didn’t Julie come to meet us yesterday? She must have been working.
• Why didn’t Julie come to meet us yesterday? She can’t have been sleeping.
Using ‘should’ for logical necessity
We can also use ‘should’ and ‘ought to’ for logical necessity. They are slightly different from ‘must’.
We believe the statement to be true because of evidence or our experience, but they are less certain.
They mean ‘if everything else is normal, then this is true’. It’s a kind of reasonable assumption. We don’t use ‘should’ or
‘ought to’ for unpleasant things.
• He should be at home now. He left ages ago.
• She shouldn’t be at work now – normally she leaves at five.
We can use ‘should (not) have + past participle’ and ‘ought (not) to have + past participle’ to talk about the past.
• She should have arrived this morning.
We can use ‘should / ought to’ for things that are in fact not true, but we think normally would be the case. We can’t use
‘must’ like this.
• The plane ought to have arrived by now, but it hasn’t.
• NOT: The plane must have arrived by now but it hasn’t.
We can also use the continuous infinitive with ‘should’ and ‘ought to’.
• She should be working now.
6: Modals of Probability
We use ‘could / may / might’ to talk about logical probability. That is, how likely or probable we think something is, depending on our knowledge. Usually, this isn’t something that we can control – we are just giving our opinion about whether we think it’s likely or not. In this case, ‘could’, ‘may’ and ‘might’ are all used to mean a medium level of probability.
Present probability
In all of these cases, I don’t know for certain if she is at home or not. But I think it’s possible that she’s at home.
• She may be at home.
• She might be at home.
• She could be at home.
(Some people think that ‘could’ and ‘might’ are less likely than may, because they are considered past and so more tentative, but not everyone thinks this.)
We can also use ‘may not’ and ‘might not’. These are also both talking about a medium level of probability. We don’t use
‘could not’ like this.
• She may not be at home. (= maybe she isn’t at home)
• She might not be at home. (= maybe she isn’t at home)
We can use the continuous infinitive to talk about things that we think are happening now.
• She may (not) be working now • She might (not) be working now.
• She could be working now.
Future probability
We can also use ‘may / may not / could / might / might not’ for the future. We often use a time expression to make it clear when we mean.
• She may be at home later.
• She might not be at home later.
• She could be at home later.
We often prefer the continuous infinitive when we’re talking about the future. This is because there might be ambiguity.
In the case of ‘may’, for example, the ambiguity is with giving permission.
• You may go to the meeting tomorrow. (I give you permission to go.)
• You may be going to the meeting tomorrow. (It’s likely that you are going.)
‘May well’ suggests a strong probability.
• She may well be at home.
‘May’ is not normally used for questions about probability, but can be used in negative or indirect questions. ‘Could’ and
‘might’ can be used normally in all kinds of questions.
• NOT: may she be at home?
• Do you think she may be at home?
• May she not be at home?
Past possibility
We use ‘may (not) / might (not) / could + have + past participle’ to talk about probability in the past.
In this case, we don’t know if the things happened or not.
• Where was Julie last night?
• She might / may / could have been at home. (I’m not certain if she was at home or not.)
We use ‘may (not) / might (not) / could + have + past participle’ in the same way that we use the present perfect – something that maybe happened in the past that has a result in the present.
• I tried emailing Julie but there was no answer. She might have already left.
We use ‘may (not) / might (not) / could + have + been + verb-ing’ to talk about something that maybe was in progress at another time in the past.
• She might have been leaving when we called.
We can also use ‘may (not) / might (not) / could + have + past participle’ in the same way that we use the future perfect tense.
• By the end of the week, she might have finished the report.
Less commonly, we can use ‘may (not) / might (not) / could + have + been + verb-ing’ in the same was that we use the future perfect continuous tense.
• Julie could have been working all day – we should buy some dinner on the way home later.
Hypothetical probability in the past
We also talk about things that were probable or possible in the past but that didn’t happen using ‘might (not) / could + have + past participle’. This time we know it didn’t happen.
• We might have missed the train (but we didn’t miss it).
• We could have hurt ourselves! (But we didn’t hurt ourselves.)
Sometimes we use an expression like this to be critical.
• Why did you do that? You might have been killed!
This is different from ‘he might have gone home’, which is normal probability in the past and where I don’t know if he went home or not. The structure of the sentence is exactly the same, so we need to understand from the context (and it’s not always clear) if the thing didn’t happen or if we don’t know.
7: Modals of Ability and Possibility
Present ability and possibility
We use can and can’t to talk about a present or general ability or skill (or lack of ability). The meaning is something like
‘know how to do something’.
This is especially common with the verbs ‘speak’ or ‘play’ when we’re talking about languages, instruments, games and sports.
• She can speak Italian.
• He can play the piano.
• She can’t speak English.
We can also use can to talk about something that we succeed in doing in the present moment.
• Look – I can lift the wardrobe!
We can also use ‘can’ with a specific possibility meaning. Here ‘can’ doesn’t mean that you know how to do something, but rather that circumstances let you do something or something is possible because of something external.
• I can swim. (= I know how to swim.)
• I can pick up the children tomorrow. (= Circumstances let me pick up the children / it’s possible for me to pick up the children because there is a train at the right time and my meeting will be finished.)
We often use this meaning of ‘can’ with inanimate objects. A feature of the object makes something possible.
• The car can go 150km per hour.
• This room can hold two hundred people.
Future ability and possibility
We don’t usually use ‘can’ for ability in the future when we’re talking about skills or things we’re learning how to do.
Instead, we use ‘will be able to’. An exception is in subordinate clauses where we can use the present simple with a future meaning – in this kind of clause, we can also use ‘can’. (See the lesson about the present simple in Terrific Tenses.)
• I’ll be able to speak French after my French course.
• NOT: I can speak French after my French course.
But it’s okay to say.
• I’ll come to visit you in Paris when I can speak French.
When we’re talking about possibility (being able to do something because of circumstances), we can use ‘can’ or ‘will be able to’.
• I can come and get you later.
• I’ll be able to come and get you later.
• I can’t pick you up tomorrow.
• I won’t be able to pick you up tomorrow.
Past ability and possibility
We use ‘could’ and ‘couldn’t’ in the past to talk about general ability (= know how to do something / have the skill to do something). We can also use ‘was / were able to’.
• I could read when I was six.
• I couldn’t read when I was two.
• He could always persuade his mother to give him money.
However, when we’re talking about ability on one specific occasion in the past, then we don’t use could. Instead, we need to use ‘managed to’ or ‘was / were able to’.
• I looked everywhere but I couldn’t find my keys.
• NOT: I looked everywhere and I could find my keys.
• I looked everywhere and I managed to find my keys.
• I looked everywhere and I was able to find my keys.
This is the same with possibility (being able to do something because of circumstances). We don’t use ‘could’ for one specific instance.
• NOT: I could arrive early to help last week.
• I was able to arrive early to help last week.
• I couldn’t arrive early to help last week.
• I wasn’t able to arrive early to help last week.
However, if there is a negative adverb or a question, or if we succeed only with a lot of difficulty (often with words like
‘only’ or ‘just’), we can use could for a specific past ability.
• I was so tired I could hardly finish the race. • Could you move the wardrobe by yourself?
• I could just reach the top shelf.
• She could only find one sock.
We can also use ‘could’ for specific past ability / possibility in some subordinate clauses.
• I’m really pleased that you could make it.
Conditional and hypothetical ability and possibility
We can use ‘could’ to talk about present or future ability if we are using an unreal conditional or talking about something that’s hypothetical.
• You could pass the exam if you just stayed at home and studied.
• With enough time, I could do it myself. (But I don’t have enough time.)
It’s the same for things that are hypothetically possible.
• I could meet you at eleven, but I’d be really tired the next day.
This also works for things that are impossible because we really, really don’t want to do them.
• I couldn’t touch a snake!
Unrealised past ability or possibility
In a similar way to other modal verbs with ‘have + past participle’, we can use ‘could have + past participle’ to talk about a past ability or possibility that we didn’t use.
• I could have gone to art school, but my parents didn’t want me to. (= I would have been able to go, but I didn’t go.)
• I could have gone to the gym yesterday, but I was feeling lazy. (= It was possible for me to go, but I didn’t go.)
This structure can also be used to criticise people. It means something like ‘you had the ability or possibility to do something, but you didn’t do it and that wasn’t right’.
• You could have called me to say you’d be late! I was worried. (= You were able to call me but you didn’t. You should have called me.)
Emphasise effort or feelings in the past
We can use ‘couldn’t + have + past participle’ with a comparative to show that some action was the most possible. This is usually used to show something is very true.
• I couldn’t have been more pleased! (= I was the most pleased that it’s possible for me to be = I was very, very pleased.)
• She couldn’t have worked harder. (= It was impossible for her to work any harder = she worked very, very hard.)
• She couldn’t have been more helpful. (= She was very, very helpful.)
General or typical possibility
We also use ‘can’ to say that something often happens or is possible in a certain situation. It’s similar to talking about a typical characteristic of something.
• London can be cold in June.
This means that ‘sometimes London is cold in June’ or ‘it’s possible for London to be cold in June’.
We use ‘can’ to talk about theoretical or general possibility, not probability (the chance of something happening). For probability, we use ‘may / might / could’.
• The train might be late today. (= There’s a chance that the train will be late today.)
• NOT: The train can be late today.
• Trains can be late. (= Sometimes trains are late.)
We use ‘could’ for the past of this use of ‘can’.
• My village had only one bus an hour and the bus could be very late.
• It could snow in June in Scotland 100 years ago.
Perception verbs
‘Can’ is often used with certain verbs: see / hear / smell / feel / remember / guess / tell (when it means ‘understand’).
When talking about perception – when we don’t try to do the action but it just happens automatically - these verbs aren’t usually used in the continuous. Instead, we often use them with ‘can’, especially in UK English.
• I can smell smoke.
• I can’t see our house – am I looking in the right direction?
• I can’t remember.
This is different from the ability meaning of ‘can’. ‘I can smell’ often doesn’t mean that the person has the ability to smell (though we can also use ‘can’ in that way ‘I can’t smell – I’ve got a horrible cold’). Instead, we usually use ‘can’ in this way when we are talking about something that’s happening at this moment. It means that it’s possible for me to smell something particular because of the circumstances. And it’s used in a similar way to the present continuous, to emphasise that something is happening now.
With perception verbs in the past, we use ‘could’ and ‘couldn’t’ (even for one specific instance).
• I could smell smoke, so I called the fire brigade.
• She couldn’t see the house form the top of the mountain, because it was foggy.
There’s not a huge difference in meaning between using ‘can / could’ here and using a normal tense of these verbs. But it’s more natural to use ‘can / can’t / could / couldn’t’, especially with see / hear / smell / taste.
8: Modals of Prediction
(This section repeats some material from the Terrific Tenses course. You can learn more about ‘will’ there.)
Predictions about the future
It is possible to use ‘will’ to make a straightforward prediction of the future, without the other meanings that the other modal verbs have. This is sometimes called ‘will for a simple future fact’. Of course, we can never be absolutely certain about what will happen in the future, but if we use ‘will’, it suggests that we are as sure as possible. The subject of this kid of prediction is often something other than ourselves, because we can control (a bit at least) what we do, whereas this is a prediction about things that we can’t control.
• The sun will set at 5:48.
• She’ll be four next month.
• When will the party start?
We can make ourselves sound more or less sure by using words like ‘certainly’ or ‘probably’ with ‘will’.
• The Conservatives will certainly win the election.
• It’ll probably rain this afternoon.
We can use ‘will + be + verb-ing’ (the future continuous) to talk about things we predict will be in progress in the future, and to avoid ambiguity with the other meanings of ‘will’ (like volition, for example).
• It’ll be raining when we leave the house.
• Will you be going to the party? (Avoids ‘will you go to the party?’ which can mean ‘do you want to go?’ and instead means ‘is it already planned for you to go?’.)
We can use ‘will + have + past participle’ (the future perfect) and ‘will + have + been + verb-ing’ (the future perfect continuous to make predictions about things that will be finished before another point in the future or that will continue up to another point in the future.
• Will the rain have stopped before we get home?
• The teenagers will have been studying for hours – they’ll be tired.
‘Will’ for prediction is very close to the logical necessity meaning of modals. It’s also important to mention that the distinction between prediction and willingness isn’t always clear.
• She’ll come later = she is happy to come later.
• She’ll come later = I predict she will come later.
We can also use ‘be going to’ to make predictions about the future. Sometimes we can use ‘will’ or
‘be going to’ with no difference in meaning, and native English speakers often choose one or the other for no particular reason.
We tend to use ‘be going to’ when we’re making a prediction about something in the future that is the result of something we can see in the present but which isn’t something that the speaker can control.
• It’s going to snow. (‘It will snow’ is a prediction, but isn’t usually based on something we can see now.)
• You’re going to get wet
Prediction from the viewpoint of the past.
We use ‘would’ to talk about a prediction of the future that somebody made in the past.
• She would go on to become the Prime Minister. (If I was talking about the future, I would use
‘will’ here. But instead this prediction was made in the past.)
Conditional and hypothetical predictions
We use ‘will’ in the first conditional, which is a ‘real conditional’ and so it talks about a prediction that’s not hypothetical.
‘Will’ very often has a conditional feeling about it, and sometimes the condition isn’t said, but instead we need to understand it from the situation.
• If we go early, the roads will be quiet. (= normal first conditional)
• Let’s arrive early. That’ll give us time to relax. (= if we arrive early, we’ll have time to relax)
• You can’t go out like that! You’ll freeze! (= if you go out like that, you’ll freeze).
Of course, we also use ‘would’ in unreal conditionals, when we are making hypothetical predictions about the future.
• If we went early, the roads would be quiet.
• We should go early. That would give us time to relax.
9: Other Uses of Modals
Characteristic or typical behaviour in the present
We can use ‘will’ to talk about things that are very predictable because we know how a person or a thing usually behaves.
Even though we are talking about the present (or about timeless facts), we use can use ‘will’. We can also use the present simple in the normal way.
• She’ll read for hours if she is alone.
• Politicians will always vote for tax cuts.
We often use will in this way to talk about how materials behave or about how big or fast something is.
• Hot air will always rise.
• The classroom will hold thirty students.
If we want to criticise someone’s characteristic behaviour, we can stress will. We don’t usually use the present simple for this kind of use, as it’s neutral, but we also use the present continuous. See the lesson on the present continuous for more information.
• Julie WILL always forget her wallet and then I have to pay.
• I love John, but he WILL smoke such a lot.
This is quite common with inanimate objects – it’s as if we’re saying they also have characteristics.
• My computer will take hours to update.
• The piano simply won’t stay in tune.
Characteristic or typical behaviour in the past
We can use ‘would’ (in this case it can be understood as the past of ‘will’) in the same way to talk about the past. We often use a time expression to make the meaning clearer.
• Lucy would read for hours when she was a child.
• After school, we would walk along the river to get home.
We can stress ‘would’ to criticise someone’s typical behaviour in the past, in the same way that we use ‘will’ for the present. Even if the behaviour happened only once, we can still use ‘would’ because it means something like ‘that is what I expect of you’.
• John WOULD be late for the meeting!
• She WOULD always leave her keys at home.
The way that we use ‘will’ to make guess about the present in a similar way as for logical necessity is sometime because of our knowledge of these characteristics. (See also the section on Modals of Logical Necessity.)
• Lucy will be at home at the moment.
• Don’t call them now – they’ll be having dinner.
We can also use will + have + past participle to talk about something similar in the past.
• Don’t call them now – they’ll have gone to bed.
Characteristic behaviour and can
‘Can’ is also used to talk about characteristic behaviour, particularly negatively.
• He can be very impatient. (= Sometimes he is very impatient.) In the past, we can use ‘could’.
• He could be very impatient
Modals of Concession
(Can be paraphrased with “although”)
We use ‘may’ and ‘might’ for concession. When we use them this way, they add the meaning of ‘although’ to the sentence. We mention a fact, and then say that it isn’t relevant to what we’re talking about. Here, ‘may’ and ‘might’ are talking about something that is true, not something that might be true. This type of clause is often followed by ‘but …’.
• She may be rich but she’s not happy (= although she is rich, she’s not happy).
• London might be busy but there are lots of peaceful parks (= although London is busy, there are lots of peaceful parks).
We can use ‘may / might + have + past participle’ for the same meaning in the past.
• She may have been at the party, but she didn’t talk to me!
• He might have gone to Cambridge, but he can’t write a decent paragraph.
Should in subordinate clauses
We can use ‘should’ in some subordinate clauses. Mostly these express some kind of surprise or stressing that something is important. This use of ‘should’ is quite formal and old fashioned.
After adjectives like: important / necessary / vital / essential / eager / anxious / concerned / ridiculous / astonishing
• It’s ridiculous that she shouldn’t come!
After verbs like: insist / recommend
• I insist that he should get a new job immediately.
After nouns like: reason
There’s no reason she shouldn’t work here.
