could not

/kʊd nɒt/

was unable to

She could not attend the meeting due to illness.

She was unable to go to the meeting because she was sick.

general

Used to express inability or impossibility in the past or present.

I could not solve the problem on my own.

I was unable to figure out the problem by myself.

The machine could not process the data correctly.

The machine was unable to handle the data properly.

Often used to emphasize a lack of ability or permission.

Collocations

could not help butwas unable to avoidcould not standfound something unbearable

was unable to avoid

found something intolerable

In informal contexts, 'couldn't' is often used instead of 'could not'.

'Could not' is used to negate the ability or possibility of an action in the past or present.

Derived from the modal verb 'could' (past tense of 'can') combined with the negation 'not'.

Commonly used in formal and informal contexts to express inability or refusal.

could

past tense of 'can'

root

not

negation

suffix

English Dictionary