CLASS RULERS

Obligetion:                                              Phohibition:
You must be silent                                            You mustn't speak in classroom.
You must listen to the teacher                            You mustn't chew gum in
You must work in class                                      classroom.
You must pay attention                                     You mustn't play computer
                                                                     games in classroom.
                                                                     You mustn't shout in classroom.