Мне . надо написать школьные правила и там должно быть слово mast и mas not

Во-первых must и must not.
1) You mast do your homework
2) You mustn’t make noise
3) You must listen to your teacher
4) you mustn’t talk to your classmates on the lesson
5) You mustn’t use your mobile phone on the lessons
6) you must study hard
7) you must wear a school uniform
8) You must come to school on time