1. 1. Helen was reading a magazine when her younger sister called her.
2. I was shopping when my friend went to the cafe.
2. 1. My mother was cooking in the kitchen while i was doing homework.
2. Our kids were playing games while we were preparing our works.
3. 1. At 5 o`clock yesterday i was talking with my mother about exams.
2. At 3 o`clock last Sunday i was walking with my dog.