can't

Meanings

1. 1modal verb

   Be unable to do something; not have the ability or possibility to do something.

   Grammar: Followed by the base form of a verb: I can't swim. No 'to' before the verb.

   Patterns

   • can't do something
   • can't be something
   • can't have done something

   I can't come to the party tonight because I have to study.

   She can't speak French very well yet.

   We can't afford a new car this year.

2. 2modal verb

   Be not allowed to do something; used to say that something is forbidden or not permitted.

   Grammar: Often used for rules or prohibitions: You can't park here. In formal writing, 'cannot' is preferred.

   Patterns

   • can't do something
   • can't be done

   You can't park your car on this street between 8 a.m. and 6 p.m.

   Visitors can't enter the lab without permission.

   You can't smoke in the restaurant.

3. 3modal verb

   Used to say that something is impossible or very unlikely.

   Grammar: Often used in exclamations of disbelief: That can't be true!

   Patterns

   • can't be true
   • can't be right
   • can't have been

   That can't be true—I saw him yesterday.

   She can't have finished the report already; it was due tomorrow.

   It can't be that difficult; even a child could do it.

Common combinations

can't help

I can't help laughing when I see that video.

can't stand

He can't stand waiting in long lines.

can't wait

I can't wait to see you next week!

can't afford

We can't afford to buy a house right now.

can't believe

I can't believe she said that.

Synonyms and how they differ

cannot

Cannot is the full, formal form; can't is informal and more common in speech and casual writing.

unable to

Unable to is more formal and often used in writing; it means not having the ability to do something, but it is not a modal verb and needs 'be'.

Opposites

Commonly confused: can't or cant?

Practice

Make it your own

Write a sentence using “can't”, then check it and compare it with the examples above.

Explore more words