Modal Verbs – Can

“Can” is used to express ability and also it is used to ask for informal permission.
(usually at home or with friends)

  • They can really play football well. (ability)
  • She can dance all night long. (ability)
  • He can play the piano. (ability)
  • Can I go and see my friends? (informal permission)
  • If I do the dishes, can I watch my favorite program? (informal permission)
  • Can I shut the door, it’s awfully cold in here? (informal permission)

Questions with “can” when asking about abilities.

Question: Can he speak Russian?
Affirmative answer:
 Yes, he can.
Negative answer:
 No, he can’t.

Question: Can she really fly an airplane?
Affirmative answer:
 Yes, she can.
Negative answer:
 No, she can’t.

Question: Argentina is really a good team, but can they win The World Cup?
Affirmative answer:
 Yes, they can.
Negative answer:
 No, they can’t.

Question: Can you really speak five languages fluently?
Affirmative answer:
 Yes, I can.
Negative answer:
 No, I can’t.

Question: Can Superman really bend steel with his bare hands?
Affirmative answer:
 Yes, he can.
Negative answer:
 No, he can’t.

For the ability with “can” the structure is as follows:

 Subject  + Can  + Verb in Infinitive Form  + Complementizer
I
 can
 swim
 twenty miles easily.
You
 can
 paint
 really well.
She
 can
 play
 baseball.
He
 can
 speak
 Russian.
It
 can
 jump
 over the fence.
We
 can
 beat
 the other team.
You
 can
 come
 to the party.
They
 can
 work
 really fast.

Can” Can is also used much in the same way as “may” is used when asking for permission or making a request, but it is used less formally. Usually “can” is used among friends or at home.

  • Can I
     go to the beach after I’m finished with my homework?
  • Can we
     play football with you guys?
  • Can you
     please shut the window?
  • Can you
     please pass the salt?
  • Can I
     see those pictures you’re looking at, they look really interested?

When asking for permission or making a request with “can” the structure is as follows:

 Can  + Subject  + Verb in Infinitive Form  + Complementizer
Can
 I
 visit
 them next summer?
Can
 you
 call
 me later?
Can
 he
 go
 with us?
Can
 she
 come
 to my party?
Can
 it
 sleep
 in tomorrow?
Can
 we
 sleep
 in tomorrow?
Can
 they
 borrow
 our car tonight?

The negative form of “can” is “can’t” when using “can’t” for abilities. It is also used as a negative answer when asking for permission or a request.

 Subject  + Can’t  + Verb in Infinitive Form  + Complement
I
 can’t
 swim
 well.
You
 can’t
 speak
 Japanese.
He
 can’t
 dance
 at all.
She
 can’t
 pay
 the violin.
It
 can’t
 jump
 the fence.
We
 can’t
 go
 to the dance.
You
 can’t
 copy
 the exam.
They
 can’t
 buy
 that car yet.

Examples of “can’t” as a negative answer to polite requests and asking for permission.

Request: Mother, can I go to the movies later?
Answer:
 No, you can’t.

Request: Can I borrow your pen for a second?
Answer:
 No you can’t because I need it now.

Request: Sir, can I talk to you for a second?
Answer:
 No you can’t, I’m terribly busy.

Request: Mom, can I watch a movie on TV tonight?
Answer:
 No you can’t, you have a lot of homework to do.

Request: Maria, can I have your telephone number?
Answer:
 No you can’t, you’ve already asked my younger sister, my best friend and for Sylvia’s number.