Ответ:

1. When i came home, my little sister was sleeping

2. When Nick came home, his brother was playing with his toys

3. When mother came home, i was doing my homework

4. When father came home, Pete was sleeping

5. When mother came home, the children were playing on the carpet

6. When i got up, my mother and father were drinking tea

7. When i came to my friend's place, he was watching TV

8. When i saw my friends, they were playing football

9. When i opened the door, the cat was sitting on the table

10. When Kate opened the door, the children were dancing round the fir-tree

11. When Tom was crossing the street, he fell

12. When i was going to school, i met my friend

13. When we were going to the cinema, we met grandmother

14. When grandmother was going home, she saw many children in the yard

15. When Henry was walking about in the forest, he found a bear cup

16. When we were walking about in the forest, we saw a hare

17. When i was washing the floor, i founf my old toy under the sofa

18. When granny was reading a book on the sofa, she fell asleep

19. When i was playing in the yard, i suddenly saw my old friend

20. When Nick was running about in the yard, he fell