1. You must do your homework.
2. You mustn`t watch TV so much.
3. You must clean your room.
4. You mustn`t go to bed so late.
5. You must clean your teeth.
6. You mustn`t eat so many sweets.
7. You must practise the piano.
8. You mustn`t play so many computer games.
9. You mustn`t talk in the lesson.
10. You mustn`t chew gum when you talk.
11. You mustn`t come home so late.