1. We were listening to a lecture yesterday at ten o'clock.
2. She was playing the piano from 11 till 12 o'clock.
3. When he came in, I was doing my exercises.
4. What were you doing yesterday at 8 o'clock?
5. Yesterday when I was reading the newspaper, my sister was listening to a concert over the radio.
6. She was looking out of the window when I saw her.
7. I was walking along the street with my friend when the car passed by.
