Create nouns from the following verbs:

1. to assume

2. to change

3. to succeed

4. to expand

5. to feel

6. to give

7. to prefer

8. to increase

9. to sell

10. to hint

11. to prove

12. to conceive

13. to lose

14. to remove

15. to stimulate

16. to render

17. to perceive

18. to release

19. to use

20. to heal