CAN vs COULD! Do you know how to use modal verbs CAN and COULD correctly? Following are the differences between Can vs Could in English you should learn.
How to Use CAN vs COULD
General Structures of CAN vs COULD in a Sentence
POSITIVE FORM (+) : Subject + CAN/COULD + Verb ( first form of the verb )
NEGATIVE FORM (-) : Subject + CAN/COULD + NOT + Verb ( first form of the verb )
QUESTION FORM (?) : CAN/COULD+ Subject + Verb ( first form of the verb )
Using COULD vs CAN
CAN is used to express that someone is able to do something. ( Present Ability )
- I can speak four languages.
- She can drive a car.
COULD is used to express that someone is able to do something in the past. ( Past Ability )
- He could play football well when he was a kid.
- We could not ( couldn’t ) get a job at those times.
CAN is used to express that something is possible. ( Present Possibility )
- Alcohol can cause cancer.
- They can stay with us when they come.
COULD is used to express that something is possible in the past. ( Past Possibility )
- A lot of crime could be prevented.
- This new method could be an important step in success.
CAN is used to ask or give permission for something. ( Informal Permission )
- Can I use your book, please? ( ask for permission )
- If you want, you can go to the park. ( give permission )
COULD 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?
CAN is used in a question, which is not a real question, to ask somebody to do something. We want somebody to do our request ( in an informal way, especially between friends or family ). ( Informal Request )
- Can you make me coffee?
- Can you hand me the pen?
COULD 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?
CAN is used in offers to help someone or to do something for someone. ( Informal Offer )
- Can I help you?
- If they like, I can carry some bags for you.
COULD 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.
For CAN NOT
It is used in negative saying ( when we are sure that something is not true or something is surprising )
- It can’t be raining. The sun is shining and there are no rain clouds.
( The speaker means that s/he is sure that it isn’t raining because the sun is shining and there are no rain clouds.)
It is also used in negative saying ( when something is forbidden or not allowed )
- You can’t park the car there.
For ” COULD NOT”
It is used in negative saying ( when something is impossible to happen or untrue)
- He couldn’t have this house. He is poor.
( The speaker means that it’s not or it might not be possible because the sun is shining and there are no rain clouds.)
For “COULD” AS A CONDITIONAL FORM OF “CAN”;
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.