Ответ:
1.Nick showed the teacher the picture which he had drown.
2. The boy gave the girl the flowers which he had brought from the field.
3. Mother saw that Nick had not wished his hands.
4. I knew that my friend had not come yet.
5. When I woke up yesterday, parents have already gone to work.
6. The children thought that his father had not come yet.
7. Mary told us that she had cooked a good dinner.
8. Yesterday I found the book which I had lost in summer.
9. When we come to the station, the train have already left.
10. I had finished my test by the lesson was over.