Speculation and deduction: Modal verbs and expressions — Exercise 3

1I’m sure he left early. (must) He early.

2Perhaps she is working late tonight. (might) She late tonight.

3I’m certain they didn’t understand the instructions. (can’t) They the instructions.

4Maybe he forgot to call you. (could) He to call you.

5I’m sure she is at home now. (must) She at home now.

6Perhaps they were sleeping when you called. (might) They when you called.

7I’m certain he didn’t see the message. (can’t) He the message.

8Maybe she is feeling sick today. (may) She sick today.

9I’m sure they finished the project already. (must) They the project already.

10Perhaps he is not telling the truth. (might) He the truth.