Modal Verbs – “COULD”


COULD” is one of the most used modal verbs in English. “COULD” is an auxiliary verb ( modal auxiliary verb ). 

It can be used to express;

  • Ability
  • Possibility
  • Permission
  • Request
  • Suggestion 

General Structure of  “COULD” in a Sentence

POSITIVE FORM (+) :  Subject + COULD + Verb (  first form of the verb )

NEGATIVE FORM (-) : Subject + COULD + NOT ( CAN’T ) + Verb (  first form of the verb )

QUESTION FORM (?) : COULD+ Subject + Verb (  first form of the verb )


  • I could say something. ( positive form )
  • I could not ( couldn’t ) say something. ( negative form )
  • Could I say something? ( question form )


Contraction for ” COULD NOT “;

could not –> couldn’t   Ex: I couldn’t speak to Mr. Big.


The negative form “couldn’t” is generally used in spoken English and “could not” is generally used in written English.

Using ” COULD “

COULD and/or COULDN’T” is used as the past tense of “CAN and/or CAN’T“.

1. It is used to express that someone is able to do something in the past. ( Ability in the Past)


  • I could speak four languages when I was younger.
  • She could not ( couldn’t ) drive a car.
  • He could play football well when he was a kid.
  • We could not ( couldn’t ) get a job at those times.

2. It is used to express that something is possible in the past.  (  Possibility in the Past )


  • A lot of crime could be prevented.
  • This new method could be an important step in success.
  • I could call you anytime.

3. It is used in a question, which is not a real question, to ask somebody to do something in a polite way. “COULD” is used as a more formal and polite form of “CAN”. ( Polite Request )


  • Could you lend me this book?
  • Could you tell me where the post office is, please?
  • Could you turn that music down a little, please?
  • Could you please explain this to me one more time?

4. It is also used to ask or give permission for something. “COULD” is used as a more formal and polite form of “CAN”. ( Polite Permission )


  • Could I take your book, please? 
  • Could I please use your computer?
  • Excuse me, could I just ask you something? 
  • Could we go home now?

5. It is used for making a suggestion. ( Suggestion )


  • If you want,we could go out for dinner after school?
  • You could always call me every day of the week if it is necessary.
  • You could go out for relax.
  • I could help you with Spanish if you are interested.



When we are talking about past time in conditionals, we use “could” instead of “can”.


  • If you called me, I could find you some suggestion.
  • I could visit many places if I had more money.
  • Even if I had more time, I couldn’t study hard.

For ” COULD + HAVE + V3 “;

1. It is used to express a possiblity in the past.


  • I can’t my key. Where could I have put it?
  • They were lucky because they could have died but they didn’t.
  • The computer is closed.  The students could have turned it off.
  • Where is Susan? I don’t know she could have fallen asleep.

2. It is used to express unrealised past ability. It means that someone has ability to do something but she/he didn’t try to do it. We can say that it is a form of critism.


  • could have bought a new house but I didn’t buy.
  • You could have told us about this. Why didn’t you?
  • We could have learned to play any musical enstruments last year.
  • She could have spoken any languages she wanted.


It is used in negative saying ( when something is impossible to happen or untrue)


  • He couldn’t have this house. He is poor.
  • It couldn’t be my book. I wrote my name at the top of the first page.
  • He couldn’t draw this picture. He is not good at drawing.

 For Modal Verb – CAN, click here