1)They were waiting for a bus, when it began to rain.
2)She had an accident, when he fell off the ladder.
3)He was cleaning windows, when somebody knocked the door.
4)She saw a shark, while she was swimming in the sea.
5)I didn't wear my shoes, when I cut my foot.
6)I was taking a shower, when she was driving home.
7)He was sleeping, when the spider bit him.