Page 86 - Oxford_Grammar_for_Schools_4_SB

Can, could, be able to

can use can, could and be able to for ability, permission and requests.

Ability

We use can to talk about ability. When we are talking about the past, we sometimes
I can play the piano. use was able to instead of could.
Ed can't answer the question.
We use could/couldn't to talk about a general ability
Can Julia sing well? Yes, she can.
in the past.
The past form is could/couldn't. When I was young, I could swim 1,500 metres.
My dad could run fast when he was young. BUT
I couldn't speak English ten years ago. We use was able to when we talk about one
particular action in the past. Note that in the negative,
Can doesn't have an infinitive form. So we use be able
we can still use couldn't.
to with auxiliary and modal verbs (e.g. have, will, must).
He fell off the boat but he was able to swim to the beach.
You must be able to swim.
He couldn't get the bus home because he didn't have any
You must can swim.
money.
Computers will be able to talk to us in the future.
OR
We haven't been oble to contact your parents.
He wasn't able to get the bus home.

O
Jenny is 25. What can Jenny do now? What could ÿ Could you do maths problems when you were
'
she do when she was 14? Look at the chart and younger? 'Yes, I could .'
'
complete the sentences with can, can t , could or 1 I use a computer when I was 14.
'
' t '
2 you cook now? 'Yes, I
couldn t .
/ '
3 I run 1500 metres when I was younger.
Age 14 Now
4 I drive a car now.
drive a car x ÿ 5 / you do maths problems now? '
' t
No, I -.
cook X ÿ
6 But I use a computer now.
run 1500m ÿ x 7 I run 1500 metres now.
8 I drive a car when I was 14.
use a computer X ÿ

do maths problems ÿ X

84 Can, could, be oble to