Can, can’t – ability, possibility, permission
Can, can’t – form
Infinitive without to
We use can + infinitive without to.
I can swim. (NOT I can to swim.)
We can’t come. (NOT We can’t to come.)
No -s after he/she/it
We don’t add -s after he/she/it. We use can for all persons.
He can swim. (NOT He cans swim).
No do/don’t
Can is an auxiliary verb and has a negative and interrogative form. We don’t use do/don’t to make questions and negatives.
Can you swim? (NOT Do you can swim?)
He can’t swim. (NOT He don’t can swim.)
Can, can’t – use
Ability
We use can/can’t to talk about ability in the present (=things that we know how to do).
Laura can sing very well.
I can’t speak German.
Possibility
We use can/can’t to ask for permission or to say if something is possible or not.
Can I sit here?
You can’t vote if you aren’t 18 years old.
I’m sorry but I can’t come to the party.
Ask for something
We use can/can’t to ask for something and to order in bars, restaurants, shops, etc.
Can you lend me some money?
Can I have some water, please?
Can I have a burger and a soda?