1) It was snowing when they went out.
2) He was playing the computer game when the door opened quietly.
3) When Alan and Tom looked at the owl, it was sleeping.
4) When she was running to school, she saw a man in black near the house.
5) I was drawing when my mother called me.
6) Suddenly he saw a big black dog. It was sitting at the door of his house.
7) The children were swimming in the lake when a strange animal jumped out of the lake.