Let's go through the sentences and determine if they are true or false:

1. You must close the door before going out.
- True

2. You mustn't do your homework.
- False

3. You mustn't obey your parents.
- False

4. You must go to school on time.
- True

5. You must walk on the grass.
- False

6. You mustn't shout at me.
- True

7. You must brush your teeth before going to bed.
- True

8. You mustn't eat fruit and vegetables.
- False

9. You must stay up late.
- False

10. You mustn't use your phone during the film.
- True

For the second exercise, complete the sentences with "must" or "mustn't":

1. You **must** help your mother with the heavy box.
2. It's very cold. You **mustn't** go out.
3. You **must** look after the house when your parents are away.
4. You **must** wash your face in the morning.
5. You **must** take your umbrella because it's raining.
6. You **mustn't** drink that milk, it's very hot.
7. You **mustn't** make noise in the class.