1. I cut my finger while I was cooking dinner
2. I  switched off the light when I was leaving home
3. The alarm clock rang while I was getting up
4. I met him when I was walking in the park
5. She left while I was dancing
6. It began raining when I was washing up after dinner
7. He rang me up when I was cooking scones for my tea party
8. She arrived when I was having dinner
9. I saw him last time when I was leaving after our dancing party
10. I caught a cold when I was airing the room
11. I broke the plate while I was carrying the dishes into the kitchen
12. She broke her arm while she was sliding on the frozen pond  

2. 1. b
2. c