1. I don't want anyone to know. You mustn't tell anyone.
2. He doesn't have to wear a suit to work but he usually does.
3. I can stay in bed tomorrow morning because I don't have to go to work.
4. Whatever you do, you mustn't touch that switch. It's very dangerous.
5. There's a lift in the building, so we don't have to сlimb the stairs.
6. You mustn't forget what I told you. It's very important.
7. Sue doesn't have to get up early. She gets up early because she wants to.
8. Don't make so much noise. We mustn't wake the baby.
9. I mustn't eat too much. I'm supposed to be on a diet.
10. You don't have to be a good player to enjoy a game of tennis.