Use Past Simple and Past Continuous.
What (they do) at 10 p. m. last night, it was really noisy?
2. When I walk) into the room, they (work)
3. It (be) a day last September. The sun (shine) and the birds (sing). I (walk) along the street when I (meet) an old friend,
4 When her train (get) to the station, we (wait) platform.​