form

present tense

affirmative	negative	interrogative
I /you /he /she /it /we /they can	I /you /he /she /it /we /they cannot / can’t	can I /you /he /she /it /we /they?

past tense

affirmative	negative	interrogative
I /you /he /she /it /we /they could	I /you /he /she /it /we /they could not / couldn’t	could I /you /he /she /it /we /they?

present tense

affirmative	negative	interrogative
I am able to	I am not able to	am I able to?
you are able to	you are not / aren’t able to	are you able to?
he /she /it is able to	he /she /it is not / isn’t able to	is he /she /it able to?
we are able to	we are not / aren’t able to	are we able to?
they  are able to	they are not / aren’t able to	are they  able to?

past tense

affirmative	negative	interrogative
I was able to	I was not able to	was I able to?
you were able to	you were not / weren’t able to	were you able to?
he /she /it was able to	he /she /it was not / wasn’t able to	was he /she /it able to?
we were able to	we were not / aren’t able to	were we able to?
they were able to	they were not / weren’t able to	were they  able to?

exercises

can and can’t  (elementary)

• exercise 1: choose can or can’t
• exercise 2: choose can or can’t
• exercise 3: fill in can or can’t
• exercise 4: fill in can or can’t
• exercise 5: choose can or can’t

 can and could (elementary)

• exercise 1: fill in can or could (ability)

to be able to

• exercise 1: fill in the correct verb forms of to be able to

Useful pages

• exercises for practising modalities: ability, permission, advice, deduction and probability, necessity and obligation and request