1. He did not go with us till he had finished his homework

2. They had met each other before they came here

3. My mother had worked as a farmer before becoming a teacher

4. We watched TV after I had finished all chores

5.Which channel had you watched before turning in this one

6. By the time we graduated, he had worked for 4 companies 

7. Because he had read this book, he did not buy it

8. I just called her to tell that they had cancelled the interview