1. When my father (came) home, I (was having) dinner.
2. When Alice (returned), I (was listening) to the radio.
3. When mother ( entered) his room, he (was drawing) a picture.
4. When my sister ( came in), I (was doing) my lessons.
5. When her aunt (was airing) the room, she (caught) cold.
6. When I ( met) her, she (was going) to the office.
7. He (was washing) his face when somebody ( knocked) at the door.
8. The young people (were dancing) when I ( came) to the party.
9. When he (was washing) the dishes, he (broke) a plate.
10. What were they ( doing) when you (saw) them?