a) -ed -  watched called filled

dc+ed -  stopped dropped

-d - dived solved

-ied - cried tried

irregular - found told took call went felt sent

b) 1 found

2 called

3 dived

4 told

5 watched

6 sent

7 cried

8 went

9 felt

10 dropped

11 took

12 stopped

13 tried

14 filled

15 solved