Can, Can´t Could, Couldn't

Can, Can´t

Could, Couldn't

PSI.

Ability in the present

Can ('t) + Infinitive

To talk about ability i nthe present, we use can, can't.

Example:

He can't ride a bike.

Can you see the mountain?

Ability in the Past

Couldn't (n't) + Infinitive

was(n't) / were(n't) able to + infinitive

To talk about general ability in the past in positive sentences, we use could or was/were able to.

Examples:

• I could swim when I was five years old

• She was able to speak English fluently when she was a child.

To talk about ability in the past on one specific occasion in positive sentences, we use was/were able to

NO (Could) X

Example:

• I was able to finish the race in less than an hour.

To talk about

general abbility in the past in negative sentences.

Use couldn't or wasn't /weren't able to

Examples:

• I couildn't ride a bike until I was 10 years old.

• He wasn't able to play the piano when he was younger.

To talk about ability in the past

on one specific ocasion in negative sentences,

we use couldn't, wasn't/weren't able to

Examples:

• The lights went out and I couldn't see anything.

• There weren't able to see the film because there wer.e no tickets left