Ответ:

students have to be at school on time. Students have to be quiet in the corridors. Students must not eat snacks in class. Students must hand in homework on time. Students have to eat in the canteen. Students must not use a mobile phone in class. Students have to wear a school uniform.

Объяснение:

слова тип: "must not" можешь заменить на "needn't"

("must not" более популярное выражение)

слово "must" использовать постоянно это некультурно!!