Talking About Ability In English

Present ability

We use can to talk about present or general ability.

• I can swim.
• She can read Italian, but she can’t speak it.

Past ability

We use could to talk about general ability in the past.

• She could read when she was four.

Note that was/were able is also possible with this meaning.

• She was able to read when she was four.

Future ability

We normally use will be able to talk about future ability.

• I will be able to speak good French in a few months.

Unrealized past ability

We use could have + past participle to talk about unrealized past ability – to say that somebody was able to do something, but did not try to do it.

• I was so angry I could have killed her.
• I could have married anybody I wanted to.

Couldn’t have + past participle means that somebody would not have been able to do something even if they had wanted or tried to.

• I couldn’t have won, so I didn’t go in for the race.