Dưới đây là các câu đã được điền động từ khuyết thiếu "must" hoặc "mustn't":

1. You **must** fight in the playground.
2. You **mustn't** make so much noise.
3. You **must** be home by 9 o'clock. The film starts at 9:15.
4. Passengers **must** do your homework.
5. You **must** talk to the driver whilst the bus is in motion.
6. This is a dangerous tour. Children **must** be accompanied by an adult.
7. People **mustn't** stand on this bus.
8. We **mustn't** cheat on a test.
9. You **must** do more exercise to stay fit.
10. There **mustn't** be something too loud.
11. We **must** help in the house.
12. We **mustn't** give up when we are so close.
13. You **mustn't** annoy your little sister.
14. You **mustn't** bite nails.
15. This was a nice evening. We **must** meet again.

Hy vọng giúp ích cho bạn!