Must you put litter in the bin?
Yes. You must put litter in the bin.
Must you pick flowers in the park?
No. You mustn't pick flowers in the park.
Must you be quiet in class?
Yes. I must be quiet in class.
Must you turn off your mobile phone in the classroom?
Yes. You must turn off your mobile phone in the classroom.
Must you throw litter on the grass?
No. You mustn't throw litter on the grass.
Must you put your books back on the shelf in the library?
Yes. You must put your books back on the shelf in the library.
Must you eat in the classroom?
No. You mustn't eat in the classroom.
Must you speak Vietnamese in an English lesson?
No. You mustn't speak Vietnamese in an English lesson.
Must you speak loudly in the library?
No. You mustn't speak loudly in the library.
Must you run in the classroom?
No. You mustn't run in the classroom.