01: 4C (some would bid 3H here, prefering to show 6 cards in a major than a fit in the minors; but you don't quite have the points for it, and 2H would be too weak)
02: 3D (it's not a reverse, so must jump to show strength)
03: 3H
04: 2H (strictly speaking, you should have opened 1NT :) )
05: 2S (reverse, so no need to jump to show strength)
06: 5C (partner has showed 9+ points and you have (including distribution) 19, good enough to try)
07: 2D
08: 2H (can't show spades, as that would be a reverse)
09: 2D
10: 2D
11: 2H
12: 1NT (15-17)
13: 3NT (should be easy)
14: 2D
15: 2H
16: 2H (annoying, but you can't bid anything else)
17: 2H (oops, you should have opened 1S, and now you can't even show them, because not strong enough for reverse)
18: 2H
19: 3H (although you probably should have opened 2NT to begin with)
20: 1NT (with one more point, you would bid 2NT)