
Level: beginner
Possibility and impossibility
We use could to show that something is possible, but not certain:
They could come by car. (= Maybe they will come by car.)
They could be at home. (= Maybe they are at home.)
We use can to make general statements about what is possible:
It can be very cold here in winter. (= It is sometimes very cold here in winter.)
You can easily get lost in this town. (= People often get lost in this town.)
We use can't or cannot to say that something is impossible:
That can't be true.
You cannot be serious.
Level: intermediate
We use could have to make guesses about the past:
It's ten o'clock. They could have arrived by now.
Where are they? They could have got lost.
We use could to make general statements about the past:
It could be very cold there in winter. (= It was sometimes very cold there in winter.)
You could easily get lost in that town. (= People often got lost in that town.)
We use can't have or couldn't have to say that a past event was impossible:
They know the way here. They can't have got lost!
If Jones was at work until six, he couldn't have done the murder.
Ability
Level: beginner
We use can and can't to talk about someone's skill or general abilities:
She can speak several languages.
He can swim like a fish.
They can't dance very well.
We use can and can't to talk about the ability to do something at a specific time in the present or future:
I can see you.
Help! I can't breathe.
We use could and couldn't to talk about the past:
She could speak several languages.
They couldn't dance very well.
Level: intermediate
We use could have to say that someone had the ability or opportunity to do something, but did not do it:
She could have learned Swahili, but she didn't want to.
I could have danced all night. [but I didn't]
Permission
Level: beginner
We use can to ask for permission to do something:
Can I ask a question, please?
Can we go home now?
could is more formal and polite than can:
Could I ask a question please?
Could we go home now?
We use can to give permission:
You can go home now.
You can borrow my pen if you like.
We use can to say that someone has permission to do something:
We can go out whenever we want.
Students can travel for free.
We use can't to refuse permission or say that someone does not have permission:
You can't go home yet.
Students can't travel for free.
Requests
We use could you … as a polite way of telling or asking someone to do something:
Could you take a message, please?
Could I have my bill, please?
can is less polite:
Can you take a message, please?
Offers
We use can I … to make offers:
Can I help you?
Can I do that for you?
We sometimes say I can ... or I could ... to make an offer:
I can do that for you if you like.
I could give you a lift to the station.
Suggestions
We use could to make suggestions:
We could meet at the weekend.
You could eat out tonight.
Questions and negatives
We make questions by putting the subject after can/could:
Can I ...? Could I ...? etc. |
Can you ...? Could you ...? |
The negative form is can't in spoken English and cannot in written English.
We sometimes say cannot, but it is very emphatic.
The negative form of could is couldn't in spoken English and could not in written English.
- can and could: possibility 1
- can and could: possibility 2
- can and could: other uses 1
- can and could: other uses 2
Hello dkbc,
Those forms are possible for all full modals; verbs like need and dare are not always treated as modal verbs, and in fact are slowly transitioning to being normal verbs rather than modal verbs. Verbs like have to and ought to are, at best, semi-modals, and used to is generally described as a marginal modal.
For some modals it's hard to imagine a context in which they would be used because of the particular meaning of the verb. For example, while can have done is a possible form, it is very hard to imagine a context in which it would be used naturally.
Peter
The LearnEnglish Team
Hi Lucas_xpp,
In your first sentence, could is used to show possibility. You could replace it with may or might but not with can, which would show ability, not possibility.
In your second example, could is used to show past ability. You could use can here, but it would change the meaning to present ability. Given that the situation is still unresolved, can works fine here.
In your third example, you could use would. Both could and would can be used in this type of polite request.
Peter
The LearnEnglish Team
Hi Anisha00329,
In the first sentence, could not shows inability in the past. You might argue that the situation (cutting jobs) is a present situation, not a past one. But by using the past form could not, the speaker frames it as a past action. It may be referring to the time that the job cuts were decided (which is a time before the current announcement, i.e. a past time).
In the second sentence, could is used to show hypothetical possibilities, not real ones. It's not claiming that this thing actually is or can be interpreted or understood in all these ways in reality.
Best wishes,
Jonathan
The LearnEnglish Team
Hi AsahiYo20,
I'll try to answer your questions in turn.
Does that make sense?
Best wishes,
Jonathan
The LearnEnglish Team
Hello Sharath.v,
It's hard to be absulutely certain without knowing the context, but I think could is necessary here because the whole sentence is in the past, as shown by the past tense verb gave.
Peter
The LearnEnglish Team
Hello Najmiii3579,
Your first sentence looks rather odd to me. I think the normal form would be either [can't be > isn't wearing] for present meaning or [couldn't be > wasn't wearing] for past.
With your second sentence, it's difficult to say for sure without knowing the context and intention of the speaker. A word might be possible in theory, but change the meaning in such a way that it is highly unlikely, and we would have to describe each context in detail to explain.
If you can tell us what you want to say (i.e. what meaning you want to convey) then we'll be happy to help you to do so.
Peter
The LearnEnglish Team
Hello cms10,
In the first sentence, both may and can are possibly alternatives to could in terms of grammar, but they change the meaning. May would tell us that the persion is allowed to play - not prohibited. Can woud be more similar to could but would make the situation more real. If we use could then the situation is hypothetical. If we use can then it suggests that he has a real possibility of playing for any team - he has offers and can choose amongst them, for example. For this reason, could is preferable in this context.
The meanings would be the same in the second sentence: may would describe what is allowed (by the rules, for example); can would describe what is possible and likely or realistic; could would describe what is hypothetically or theoretically possible.
Peter
The LearnEnglish Team
Hello cms10,
As I see it, in this sentence, 'can' is used to speak about ability -- if I replace 'can' with 'are able to', the sentence still works. The phrase 'the earliest' somehow makes it clear that the sentence is not about a possibility, but rather is more like a prediction or even promise.
To convey the idea of a possibility you're not certain about, you could use 'may', 'might' or 'could': 'We might/could/may finish it next Friday'. Notice that it doesn't work to use the phrase 'the earliest' here.
Hope this helps.
All the best,
Kirk
The LearnEnglish Team
Hello PabloTT,
Yes, you could use 'could not hear'.
To be honest, I think the best phrase here would be 'would not hear' because it expresses the intention of the person (presumably the judge) making the decision.
Peter
The LearnEnglish Team
Hi MarciaBT,
Yes! When could you start? also works fine.
The versions with may or might are possible, but less common.
Does that make sense?
Best wishes,
Jonathan
The LearnEnglish Team
Hi MarciaBT,
No problem. Yes, could shows more politeness. Since a job interview is often the first time that the people have met, that's definitely the option I would choose.
Best wishes,
Jonathan
The LearnEnglish Team
Hi AsahiYo20,
Can works fine in each sentence. However, the use is different in each example. The first sentence uses can to express possibility. The second uses can to express ability. This affects whether or not could can be used.
Even though if is not used, the first sentence is a form of conditional, expressing a condition and a dependent result. Could would make the sentences hypothetical and would require changes in the first clause:
In the second sentence, could would have a past meaning (past ability), and so the verb in the first clause would also need to be past:
Peter
The LearnEnglish Team
Hello again AsahiYo20,
The first sentence does not express future possibility but rather describes the present situation. It could be an answer to a question such as 'Why isn't the restoration work being done?', for example.
The second sentence is also not about the future. It describes a person's job in general terms, not a particular future event. It would be an answer to a question such as 'What does your job entail?' and not 'What are you doing next week?'
Peter
The LearnEnglish Team
Hi brian1010,
I can't be absolutely sure without knowing the full context of the sentence. But I think it's fine to use Nobody could ... to mean impossibility in the present because it uses could – not couldn't. If we make a version of the sentence using couldn't:
It isn't equivalent in meaning. It would be understood as referring to a past ability, not a present possibility. As you've seen above, could and couldn't have nuances in their meanings and aren't exact opposites, so could with a negative subject (e.g. Nobody could) isn't the same meaning as couldn't (for the meaning of possibility, at least).
For other meanings, could and couldn't may be more direct opposites. The sentences below about ability do have the same meaning.
Does that make sense?
Best wishes,
Jonathan
The LearnEnglish Team
Hi brian1010,
Yes, that's right. To say that those things are impossible for them to do, we can use can't or cannot, but not could not.
Using may not is possible, but the meaning is a bit different. May often indicates permission, so if we say They may not come by car, it means 'they cannot come by car because they don't have permission'. This usage of may not is also quite formal and emphatic.
Also, it might be confused with the 'not sure' meaning of may. They may not come by car (if there's no other context) would probably be understood as meaning 'I'm not sure whether they'll come by car or not', which is different from They can't come by car. So, I wouldn't recommend using may not for this meaning.
See this page for more explanation and examples about may: https://learnenglish.britishcouncil.org/english-grammar-reference/may-and-might
Best wishes,
Jonathan
The LearnEnglish Team
Hello brian1010,
Yes, you could use can in your sentence. Could has a distancing effect, making the sentence more hypothetical; can makes the sentence more immediate, as if describing a real situation. The difference is really only one of nuance, however.
I think your sentence about the earthquake may have an error. The phrase '...what might not happen...' seems odd; '...what might happen...' is more likely, I think.
Peter
The LearnEnglish Team
Hello brian1010,
Yes, somehow we missed your question -- sorry about that!
In both sentences, some might argue that 'would' speaks more of willingness and 'could' speaks more of ability, but in most cases, both forms would be correct and mean the same thing.
All the best
Kirk
The LearnEnglish Team
Hello Ballou1982
The first one implies that the main thing is whether you can or cannot come today. You don't know yet if something might stop you from coming. For example, if your friend has invited you to visit him, but you think you will have to work, you could say this because if you have to work, you can't visit your friend.
The second one is less specific. It just says that perhaps you will come or perhaps you will not. It could be due to work, it could be because you don't want to, it could be anything, really, that prevents you from coming.
Hope this helps.
All the best
Kirk
The LearnEnglish Team
Hello GIRIKUMAR,
As far as I am aware, there is no difference in meaning. Later on is a little more informal.
Later is often used as an informal way of saying goodbye, with the same meaning as See you later.
Peter
The LearnEnglish Team
Hello GIRIKUMAR,
I don't think there is a difference in meaning. Rather, there are certain typical patterns of use.
We tend to use fail in with words related to trying something: fail in your attempt, fail in your plan.
We tend to use fail at with activities: fail at the task, fail at the final test
I think fail on its own, or fail to [verb] are much more common forms, however.
Peter
The LearnEnglish Team
Hello GIRIKUMAR,
Myself can be used in several ways, as you show.
I did it myself (nobody else helped me) - this means that I did the task and nobody helped me; I did it alone.
I did it to myself (and nobody else was to blame) - this is generally used to describe unfortunate situations and it means that the speaker blames him- or herself; nobody else is responsible.
I did it for myself (not for you) - this is generally used to describe positive situations and it means that the speaker's motivation was their own benefit rather than the need or wish of someone else.
Peter
The LearnEnglish Team
Hello Girikumar
The first one is correct because we use 'to' to speak about a destination. I'm assuming that 'function' here means 'a social event', as otherwise I wouldn't really understand what these sentences mean.
Thanks! Hope you also are doing well.
All the best
Kirk
The LearnEnglish Team
Hello Girikumar
I'd probably say 'in' here, but I think both 'in' and 'at' are fine. As far as I know, there's no difference in meaning between them.
There's a good explanation of the differences in use between the most commonly used prepositions of place on this page if you're interested.
All the best
Kirk
The LearnEnglish Team