Choose the correct option to complete the sentences.

1. You can / must talk in this temple, but only if you do it quietly
2. You may / should not go to bed late if you have an early flight in the morning
3. All the hotels were full but we could / were able to find a campsite, and we stayed there
4. You don't have to / mustn't bring food if you don't want to. There is a restaurant very close by.
5. Could / Should I use the bathroom, please?