Here are the comparative forms of the adverbs from the exercise:

1. badly - worse
2. late - later
3. conveniently - more conveniently
4. smartly - more smartly
5. early - earlier
6. responsibly - more responsibly
7. far - farther/further
8. patiently - more patiently
9. fast - faster
10. generously - more generously
11. fluently - more fluently
12. cleverly - more cleverly
13. happily - more happily
14. quickly - more quickly
15. hard - harder
16. slowly - more slowly
17. well - better
18. beautifully - more beautifully
19. strongly - more strongly

Feel free to ask if you need any further assistance!