Please could you explain why you're so late.
I'm frozen - could you close the window?
I've got rather a full week next week - could we postpone our meeting?
If you could get that report finished by.
We use could have to say that someone had the ability or opportunity to do something, but did not do it:
She could have learned swahili, but she didn't want to.
The meaning of could is —used in auxiliary function in the past, in the past conditional, and as an alternative to can suggesting less force or certainty or as a polite form in the present.
How to use.
Definition of could modal verb in oxford advanced learner's dictionary.
Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.
You use could when you are expressing strong feelings about something by saying that you feel as if you want to do the thing mentioned, although you do not do it.
The english modal auxiliary verbs are a subset of the english auxiliary verbs used mostly to express modality, properties such as possibility and obligation.
[a] they can most easily be distinguished from.
The negative form of could is could not or couldn't.
To form the negative of be able to, you either put not or another negative word in front of able, or you use the expression be unable to.