how to write obligation and prohibitions

1. Read the clues,if given.Otherwise,read the question carefully and think of  what you are  allowed to do and what you are not allowed to do at the given place     
2. Write  complete sentences that express either obligations or prohibitions.
3. You had better use the following structures to express obligation and prohibitions.
4. S+should(n't) + verb 1....
5. S+must(n't)+ verb 1 ..
6. S+is /am allowed /required....
7. No +S+is/are allowed..
8. It is forbidden /prohibited to +verb 1..
9. Gerund noun (verb 4) + is(n't) allowed etc