Past, Present, Future

1.

CAN / COULD / BE ABLE TO
Past
Present
Future
could/couldn’t for past
abilities: He could play
the guitar when he was 5.
was(n’t)/were(n’t) able to
if it’s a one-time occasion:
-They were able to win
the match. // couldn’t is
also possible if negative
(e.g.: They couldn’t win
the match).
can/can’t
-I can swim. (Ability)
-The lights are off. She
can’t be at home.
(Deductions)
-Can you open the door
for me? (Request) //
Could is also possible and
more formal (e.g.: Could
you open the door for
me?)
will/won’t be able to
-They will be able to go
to the beach next
summer.