Ability - Can, could, able to
Will I (...) change these batteries if they’re the wrong type?
Will I BE ABLE TO change these batteries if they’re the wrong type?
I (...) do my homework last night. It was too difficult.
I COULDN'T/WASN'T ABLE TO do my homework last night. It was too difficult.
Daniel (...) speak French very well – nobody understands a word he says!
Daniel CAN'T speak French very well – nobody understands a word he says!