Can vs could!? Do you know the differences between two modal verbs ~ can vs could in English? Check the lesson below and find out what the differences are!
Can vs Could | Structures
Learn three forms of CAN vs COULD in English.
- Positive form (+) : Subject + can/could + Verb (bare form).
- Negative form (-) : Subject + can/could + not + Verb (bare form).
- Question form (?) : can/could+ Subject + Verb (bare form)?
Contraction for ” can not and could not “
- Can not –> Can’t
- Could not –> Couldn’t
Could vs Can | Usage
How to Use COULD vs CAN Correctly!
Can is used to express that someone is able to do something. (Present Ability)
- I can speak Chinese.
- He can swim.
Could is used to express that someone is able to do something in the past. (Past Ability)
- He could swim well when he was ten years old.
- I could not (couldn’t) get a job at those times.
Can is used to express that something is possible. (Present Possibility)
- One wrong (or false) move can lose the whole game.
- You can lead a man up to the university, but you can’t make him think.
Could is used to express that something is possible in the past. (Past Possibility)
- At worst, nuclear war could be unleashed.
- He would help you if he could.
Can is used to ask or give permission for something. (Informal Permission)
- If you need, you can take my car. (give permission)
- Can I come in, please? (ask for 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 open the window?
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 give it to me?
- Can you give me a hand?
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 open the door, please?
- Could you tell me how to do this, please?
Can is used in offers to help someone or to do something for someone. (Informal Offer)
- How can I help you?
- If you like, I can give it to you.
Could is used for making a suggestion. (Suggestion)
- If you’re free, we could go out for dinner tonight?
- You could call me whenever you want.
6. The negative form of can and could
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 have been my car. You must be mistaken. My dad drives it this morning.
(The speaker means that she/he is sure that it isn’t her/his car because her/his dad drives it this morning)
It is also used in negative saying (when something is forbidden or not allowed)
- You can’t smoke here. This is the hospital!
For ” COULD NOT”
It is used in negative saying (when something is impossible to happen or untrue)
- He couldn’t take that job at the zoo because of his epilepsy.
( The speaker means that he couldn’t take that job at the zoo because of his epilepsy)
7. 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 call me, I could help you.
- I could lend you more money if I were rich.
Can vs Could| Infographic
COULD vs CAN Differences