I mustn't eat Chewing-Gum.
I can't play video games at school.
I musn't fight at school.
I am not allowed phone at school.
I must be quiet at school.
I am not allowed to talk in class.
I have to write properly.
I musn't be insolent with teachers.
I mustn't take drugs and cigarettes to school.
I mustn't be rude in class with mates and teachers.
I am not allowed to bring weapons on school grounds.
I should listen to teachers for lessons.
I shouldn't play in the classroom.