Modal verbs: ability

 

Can is a modal verb that describes what someone is able to do. It is used in different forms to describe past and present abilities.

• Peter can cook Italian food.

 

In positive statements we put can between the subject and the main verb in its base form:

• I can ride a bicycle.
• They can help you with building your house.

 

The negative form of can becomes ‘can not’ or contracted ‘cannot’ (‘can’t’):

• Jeffrey cannot play the piano.
• She can’t go with us because she’s sick.

 

Questions with can are formed by swapping the subject and the modal verb:

• Can Jane play tennis?
• Can he drive a car?

 

Ability in the past

 

To talk about ability in the past we use could, which is the past form of can. The negative form of could is ‘could not (couldn’t)’.

• I can’t dance rumba now (present ability), but I could when I was younger (past ability).
• When I was a student I could party all night before an exam.
• I couldn’t go to that restaurant because it was too expensive.
• When Emily was eight she could play the violin.

 

Ability in the future

 

We don’t use can to describe future ability. Instead, we use ‘will be able to’:

• Peter can play the accordion quite well (present ability). In a year or two he will be able to give concerts (future ability).
• Next Sunday I will be able to see the new fountains in the park.

 

Negative statements about future ability are formed using ‘won’t be able to’ or ‘will be unable to’:

• If you don’t study well, you won’t be able to find a good job.
• Sorry, I’ll be unable to call him at 2 PM. I’ll be in a meeting at that time.