1 One day, I (sit) in the kitchen when there (be) a noise at the door.
2 Then I (jump up) and I (open) the door. There (be) nobody there.
3 Later, the telephone (ring). When I (pick up) the telephone nobody  (answer).
4 I (feel) scared when I (see) my friend through the window.
5 In the end, it (be) a joke.