Difference between Can and Could

The modal verbs can and could represent the ability of a person or thing in doing something. Can have many uses as a modal verb, but there are three uses that can be confusing to an English learner. We use could show that something is possible, but not certain. However, there is a difference in their usage, as ‘can‘ is used in the present situation, whereas we can use ‘could‘ for talking about a past ability. Both are followed by a base form of the verb. Could, of course, function as the past tense of the can, and like other past forms, it sometimes simply indicates past time: In those days there was no security and anybody could walk in, day or night. While can talks about the possibility of an event in the present situation, could is used to express a slight possibility or the possibility in the past.

Difference between Can and Could

CAN

  • Could refer to the possibility or the ability to do something.
  • ‘Can’ is a modal verb, which is used with the main verb to express the ability of a person or thing in doing something.
  • In simple words, ‘can’ means to be able or permitted to do something. It is used with the first form or the base form of the verb. Basically, it determines the ability or capability of someone or something.
  • ‘Can’ in this form, is an auxiliary verb, which means that it is used with another verb to show that the person is able to perform the action.
  • Examples: I can’t wait as I am already very late. Can you pass me the bottle?

COULD

  • ‘Can’ means be able to or permitted to do something.
  • ‘Could’ is the past participle or second form of the verb, which is used with the main verb to talk about past the ability of an individual in doing something.
  • Could is the past participle form of the verb ‘can‘ which determines the past ability of someone or something. It is also used when someone is permitted to do something.
  • The word ‘could’ means the same as the auxiliary form of the word ‘can’: the ability to do something. However, it is the past tense form of the word.
  • Examples: Anuj could have taken a taxi to reach the station. Could you give me your pen?

Both can and could are used to ask for permission and also request something, can is a more informal one, which is used when we are talking to our friends, relatives or acquaintances. However, when talking to strangers, we can use could, to ask for permission or request politely.