Homework includes of naming if the underline word is a noun or not. Need help. I’m very confused.

1. noun
2. noun
3. noun
4. noun
5. noun
6. not a noun (it's a verb)
7. not a noun (verb)
8. not a noun (adjective)
9. not a noun (adjective)
10. not a noun (verb)
11. noun
12. noun
13. noun
14. not a noun (verb)
15. not a noun (adjective)
16. not a noun (verb)
17. noun
18. noun
19. noun
20. noun