12. Since the road is wet this morning, it must rain last night.
11. I think you'd better to take his advice and rest for a few days.
10. When the storm comes all windows ought to close.
9. "You can't read that article if you don't want to."
8. Our teacher had one strict rule. She said that all the students must have come
to class on time.
7. You needn't to come to the meeting this afternoon if you have something
important to do.
6. Can I water the trees on Tuesday? No, you needn't.
5. "That must be a mistake." "No, it must not be a mistake."
4. Tell the boy that he can swimming in the river.
3. My teacher knows more than my uncle knows.