posted by Frank .
I left out the following sentences. Thank you, Writeacher.
1) You mustn't leave the school building without either your teacher's or your parents' permission.
2) You shouldn't revise for a test just the day before (the test). You shouldn't run in the corridor or raise your voice in class /during lessons/during school hours. (all possible?)
3) We don't have to come back to school in the afternoon.
4) You should make sandwiches and take them to school instead of buying a snack from the vending machines or at the school cafè/canteen.
2. Delete "revise" and insert "review" -- all else is fine.