1) I lost my keys while I was walking to school.
2) Hardly we had finished dinner when the doorbell rang.
3) He was listening to the radio while he
was preparing breakfast.
4) My father was driving at 70 km per hour when a policeman
stopped him.
5) When they came to London, they visited many museums and art galleries.
6) Cindy broke her leg while she was snowboarding.
7) After Angela had locked the door, the school bus
arrived.
8) He had met a lot of friendly people before he
moved to California.
9) While we were waiting, we were doing crossword.
10) The students opened their exercise books and
started writing.
11) What were you doing when you heard the news?
12) While the children were drawing, their parents were watching TV.
Объяснение:
