Réponse:
You mustn't eat food in class.
You must listen the teacher when he talk.
The pupils mustn't go in teacher's room.
Réponse:
We must listen to the teacher.
We mustn't chat in class.
We mustn't eat chewing-gum in class.
We mustn't run in the corridors.
we must put papers in the bin.
Explications:
MUST ET MUSTN'T sont utilisés pour dire ce que l'on doit faire (MUST) et ce que l'on ne doit pas faire (MUSTN'T) à l'école