E3:
1 helped, would do
2 would water, stayed
3 had, would buy
4 offered, would take
5 would have, lived
6 would sell, repaired
7 used, would be
8 would be, taught
9 visited, would go
10 would come, planed
E4: 
1 had checked, wouldn't have broken
2 hadn't rained, would have played
3 hadn't been, would have watched
4 bought, wouldn't have lost