MODALS (Couldn't/Might Not)

level: Intermediate (B1/B2)

Choose whether each sentence requires could not or might not.
Click on ANSWER to see the correct response.

1. We _____ contact them before we left for our trip.
a. could not
b. might not

2. I'm sorry, but I _____ be able to come today.
a. could not
b. might not

3. I'm sure that _____ have been him.
a. could not
b. might not

4. I'm not sure, but that _____ have been him.
a. could not
b. might not

5. Let's check the news. The airport _____ be open.
a. could not
b. might not

6. I _____ tell him the truth about Holly, but I should have.
a. could not
b. might not

7. Jeanette had made other plans, so she _____ come with us to the museum yesterday.
a. could not
b. might not

8. Jeanette has made other plans, so she _____ come with us to the museum today.
a. could not
b. might not

9. That incompetent lawyer _____ have possibly won that case!
a. could not
b. might not

10. She _____ have told him. That's why he didn't mention anything to me.
a. could not
b. might not

11. I _____ be able to make it to class tomorrow.
a. could not
b. might not

12. Everyone thinks he'll win, but he _____.
a. could not
b. might not

13. The news _____ have come at a worse time!
a. could not
b. might not

14. They're a good team, but they _____ win yesterday.
a. could not
b. might not

15. I'm not sure, but that _____ be the right answer.
a. could not
b. might not

Don't forget to check out our other free exercises on modals:
Mixed modals 1 (should, can, must) (I)
Mixed modals 2 (should, can, must) (I)
Modals of speculation 1 (I)
Past modals (should have, must have, etc.) 1
MODALS with the INFINITIVE 1 (B)
MODALS with the INFINITIVE 2 (B)
MODALS (Couldn't/Might Not) (I)

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