1. He had already gone by the time I came to the party.
2. Mother had cooked dinner before he came .
3. When I reached the front door, I realized that I had lost the key.
4. The shop had closed by the time Igot there.
5. The scientists carried out many experiments before they had achieved satisfactory results.
6. When I arrived , he had stayed in the same hotel where we firstmet.
7. By the end of the year he had finished research.
8. He told me that he did not see much of her since she had moved to another town.
9. When I came, he had already come and had sat near the fireplace looking through a magazine.
10. She said that they had met in 1990 for the first time.