Below are some notices and signs from a trade exhibition. Explain what each one means using may, should, shouldn’t, must, mustn’t, don’t have to. PLEASE USE OTHER DOOR You shouldn’t use this door. MEETING ROOM 6 Knock and enter 1. ______ No Photography in Main Hall 2. ______ AUTHORIZED PERSONNEL ONLY 3. ______ Present badges HERE (except staff) 4. ______ REGISTER HERE 5. ______ Events catalogue Please take one 6. ______