Ответ:

2 - ski

3 - to ski

4 - to listen

5 - listen

6 - listening

7 - learning

8 - to learn

9 - learn

10 - going

11 - to go

12 - go

Ответы на B:

2 - Learning

3 - skiing

4 - running

5 - living, living

6 - saying