In many cases, we can use either can or be able to. Note that can is more usual. In some situations can/could is not possible. For example, we cannot use can after another auxiliary verb.
Fill in the blanks with can or be able to,
1. I ............................... see something over there.
Correct!
Wrong!
2. I ............................ solve this puzzle.
Correct!
Wrong!
3. She ............................ get the promotion.
Correct!
Wrong!
4. He ........................ speak six languages.
Correct!
Wrong!
5. She will ................................. help us.
Correct!
Wrong!
We cannot use can with another auxiliary verb.
6. I have ....................................... get over that trauma.
Correct!
Wrong!
7. He ............................. finish first.
Correct!
Wrong!
8. They might .................................. win.
Correct!
Wrong!
9. The applicant must .................................... converse fluently in English.
Correct!
Wrong!
10. The fire spread rapidly but luckily we .................................. escape.
Correct!
Wrong!
We do not use could to say that we managed to do something on one occasion.
11. She played well but she ............................ win
Correct!
Wrong!
We can use either could not or was not able to to say that we could not manage to do something on one occasion.
12. I used ............................. run miles on end.
Correct!
Wrong!
Answers
- I am able to / can see something over there.
- I cannot / am not able to solve this puzzle.
- She couldn’t / was not able to get the promotion.
- He can / is able to speak six languages.
- She will be able to help us.
- I have not been able to get over that trauma.
- He was able to / could finish first.
- They might be able to win.
- The applicant must be able to converse fluently in English.
- The fire spread rapidly but luckily we were able to escape.
- She played well but she could not win.
- I used to be able to run miles on end.
