Can and Can't: Ability, Permission and Requests, With Examples and Exercises

Beginner

What are can and can’t?

Can is a modal verb. Modal verbs are a kind of auxiliary (helper) verb. They go with the main verb and add a meaning to it, for example ability, possibility or permission.

can and can't

We use can and can’t to talk about:

  • ability: things we know how to do;
  • possibility and permission: what is possible or allowed;
  • requests: when we ask for something.

Form

FormPatternExample
Positivesubject + can + verbI can swim.
Negativesubject + can’t + verbI can’t swim.
QuestionCan + subject + verb?Can you swim?

Can is the same for all persons: I can, you can, he can, she can, it can, we can, they can.

Can’t is the short form of cannot. We write it as one word.

Three rules

1. After can we use the verb without to.

Examples:

  • I can swim. (NOT: I can to swim.)
  • We can’t come. (NOT: We can’t to come.)

2. No -s after he, she, it.

Examples:

  • He can swim. (NOT: He cans swim.)
  • She can sing very well.

3. We do not use do / does with can. Can is an auxiliary verb, so it makes its own negative and question.

Examples:

  • Can you swim? (NOT: Do you can swim?)
  • He can’t swim. (NOT: He don’t can swim.)

Ability

We use can and can’t to talk about ability in the present: things we know how to do and things we do not know how to do.

UseExamples
Sports and movement
Music
Languages

Examples:

  • Laura can sing very well.
  • They can speak English.
  • I can’t speak German.
  • He can’t ride a bike.

Possibility and permission

We use can and can’t to say if something is possible or allowed, and to ask for permission.

Examples:

  • Can I sit here?
  • You can’t vote if you are under 18.
  • I’m sorry, but I can’t come to the party.

Asking for things

We use can to ask for something and to order in cafés, restaurants and shops.

Examples:

  • Can you lend me some money?
  • Can I have some water, please?
  • Can I have a burger and a soda?

Questions and short answers

For questions, we change the order of can and the subject. We can answer with a short answer.

Examples:

  • Can you swim? — Yes, I can.
  • Can she play the piano? — No, she can’t.
  • What languages can you speak?

Common mistakes

No "to" after can
Wrong: I can to swim
Correct: I can swim
No -s after he / she / it
Wrong: He cans swim
Correct: He can swim
No do / does
Wrong: Do you can swim?
Correct: Can you swim?
No do / does
Wrong: He don't can swim
Correct: He can't swim
No "to" after can't
Wrong: We can't to come
Correct: We can't come
Base verb after can
Wrong: I can speaks French
Correct: I can speak French
Base verb after can
Wrong: Can she plays piano?
Correct: Can she play piano?
Short answer with can
Wrong: Can you swim? Yes, I do.
Correct: Can you swim? Yes, I can.

Can and Can’t

GRAMMAR REFERENCE

Can / Can't

Ability, possibility, permission, requests — one form for all persons

CAN
I / you / we / they can swim
he / she / it can swim
CAN'T
I / you / we / they can't swim
he / she / it can't swim
✓ STATEMENT
subject + can + verb
I can swim.
− NEGATIVE
subject + can't + verb
He can't swim.
? QUESTION
Can + subject + verb
Can you swim?
SHORT ANSWERS
YES
Can you swim? Yes, I can.
Can she play? Yes, she can.
NO
Can you swim? No, I can't.
Can she play? No, she can't.
WHAT WE USE IT FOR
ABILITY She can sing very well.
NO ABILITY I can't speak German.
PERMISSION Can I sit here?
POSSIBILITY I can't come to the party.
REQUEST Can I have some water, please?
QUESTION WORD What languages can you speak?
REMEMBER
The verb after can has no "to" — I can swim. (not I can to swim.)
No -s after he / she / it — He can swim. (not He cans swim.)
No do / does with can — Can you swim? (not Do you can swim?)
Answer with can, not do — Yes, I can. (not Yes, I do.)

Practice exercises

Can + verb 0 / 10
Negatives and questions 0 / 10
Ability and requests 0 / 9
See all