Answer:
1. I reflected seeing him only once.
2. When I reached Leningrad I found waiting for me an urgent request that I should go to my mother's place.
3. Before leaving, I called on my friends.
4. After leaving Moscow, I corresponded with him.
5. When starting a thing like that, you don't know what you're letting yourself in for.
6. After turning the last page, she decided that she would read the book again.
7. She was a trifle out of breath upon reaching the third landing.
8. Upon reaching the restaurant, Eva found that she was the last to arrive.
9. After having had a cup of coffee and her bath, she began to feel much more herself.
10. After having taken off her theatrical make-up, she looked old and tired.
11. I suddenly remembered having seen that film.
Explanation:
