1. The students were doing an exercise
the bell rang.
2.I saw an accident
I was waiting at the bus stop.
3
she was writing an email, her computer turned off.
4. He fell down
he was climbing a tree.
5.
my mom came home, my sister was sleeping.
6. We found some old photographs
we were tidying our room.
7.
you called me last night, I was studying for the test.
8. I had a bad dream
I was sleeping on the sofa.
9.
the fire alarm went off, we were listening to music.
10. She started to cry
she was watching a movie.​