To be able to do something

To be able to do something
« to be able to » is used for ability for all tenses instead can or could.

« to be able to »: You are capable to do something.
It’s used for ability for all tenses instead can or could.
CAN and COULD (modal verbs) are used for ability.

Construction:
Subject + verb TO BE + adjective (ABLE) + TO + Infinitive:
I am able to speak english.

« to be able to do something… » is used about a specific situation.
=> express ability to do something.
=> we can use it instead CAN or COULD;
=> it’s not a modal verb!

USES:
1/ « to be able to » when we talk about ability:
You’re able to drive a car.
« Able »: adjective meaning having the power, skill (means to do something).
=> « I‘m able to swim » => « I can swim ».

2/ « to be able to … » is possible in all tenses.
I was able to speak english.
I have been able to drive…
I’m able to speak english.
I will be able to speak english.

3/ « to be able to » instead of CAN or COULD:
I’m able to drive a car = I can drive a car.
Present for ability: we use can.
I can come to visit you.
Past for ability: we use could.
He couldn’t come to visit us.
Other tenses: we use « to be able to »

4/ « to be able to » has an infinitive form (not can & could)
=> So we use it when we want to use other tenses or the infinitive.
I would like to be able to speak English.
I would like to be able to swim.
I have been able to run the marathon when I was young. (present perfect)
You will be able to speak perfect Chinese very soon. (future simple)
I would like to be able to drive a car. (infinitive)

5/ About a possibility, CAN is more common.
You can stay here if you want.

6/ will able to / won’t be able to: about the future.
I will be able to visit you tomorrow.
I won’t be able to visit you tomorrow.

 

ENGLISH CAN COULD and TO BE ABLE TO: