Bonjour pouvez vous m'aider svp je n'y arrive pas merci !

4. They must have gone away
5. I must have left it in the restaurant last night
6. The exam can't have been very difficult
7. She must have listened to our conversation
8. She can't of understood what I said
9. I must have forgotten to turn it off
10. The driver can't have seen the red light
11. The neighbours must have had a party