Adjective
1. depressed
2. not working
3. downward
4. down in the mouth
Adverb
6. toward a lower position
7. to the ground
Noun
10. soft feathers
11. down feather
12. pile
Verb
15. go through
16. pull down
17. pop
18. shoot down
19. polish
Preposition
20. to a lower position in
21. along
22. throughout