Past Continuous vs. Past Simple
Tom (fall) off the ladder while he (paint) the room.
Tom (FELL) off the ladder while he (WAS PAINTING) the room.
It (rain) while we (walk) home from work.
It (WAS RAINING) while we (WERE WALKING) home from work.
I (look)out of the window and saw that people (walk) in the park.
I (WAS LOOKING)out of the window and saw that people (WERE WALKING) in the park.