1. You mustn't be late for school.
2. You must go to the dentist with a toothache.
3. A teacher must be a patient person.
4. You musn't speak loudly in a library.
5. It's raining. You must take your umbrella.
6. You must stop when you see that sign.
7. You mustn't eat in class.
8. You must keep off the grass!
9. You must take a cough syrup once a day.
10. You mustn't tell my secret to anybody.
11. You mustn't watch too much television.
12. You must feed your pet twice a day.
13. You mustn't run with a broken leg. (Well, as a matter of fact, you can't, so...)
14. We must protect endangered species.
15. You must have a shower every day.
16. You must fasten your seatbelt in a car.
17. You mustn't forget about Mother's Day.
18. You must put the rubbish in a bin.
19. You must eat more fruit.
20. You mustn't listen to loud music after 10 p.m.
21. You mustn't eat junk food too often.
22. You must stop smoking. It's bad for you.
23. Students mustn't forget their homework.
24. You must keep the park clean.
25. You have a sore throat. You mustn't eat ice cream.
1. By 5 o’clock she has finished doing her homework.
2. We didn't know that they buy a new car.
3. We haven't plan for so many guests, so there isn't enough food.
4. When we arrived at the station, the train already left
5. She has remembered she hear the story.
6. They have refuse to go to the cinema with us, they have seen the film.
7. By 2 o’clock the lecture have finished .
8. On my way home I have bought a loaf of bread, but then I learnt that my brother buy it, too.
9. The film is more interesting than I expect.
10. I felt better after I take a pill.
2.1. The expression on his face surprised me, I never before it such saw. 2. He didn't speak to them for two days before they left. 3. Yesterday I didn't find my key because someone took it. 4. He said that he had not received an invitation. 5. He forgot where he left his umbrella. 6. I had to stay to explain what happened. 7. I was surprised when he called me, because I didn't know he was back from London. 8. The rain only stopped when we went outside. 10.at 7 o'clock, everyone is already awake.