1. He went back to get his bag, but it had been gone.
2. I was waiting for the bus when the man appeared.
3. He behaved very strangely yesterday.
4. I realised I had forgotten my passport at home.
5. He took the not, said something strange and ran away.
6. Before mother came home I had already finished doing my homework.
7. I have called six agencies. There are no tickets left.
8. Jim has been traveling since APril but he hasn't visited France yet.
9. Molly sometimes prepares something really interesting.
10. These days people are staying at home.
11. You have written so much so you can stop writing your composition.
12. He has got a very bad habit — he smokes.
13. I don't often walk in the park.
14. He hasn't lived in the house since July.
15. I haven't dated this person before.
16. He understood that Mary had lost his number.
17. When we were discussing plans for summer, our old friend came.
18. She cannot help you right now because she's sleeping.