Since или for. Урок английского языка

1. We've lived here sincefor seventeen years.

2. I haven't worked sincefor a mounth.

3. We've been together only sincefor a few days.

4. We haven't seen Mary sincefor the party.

5. I've read two books sincefor the weekend.

6. They have been ill sincefor Monday.

7. He hasn't played the piano sincefor he was a boy.

8. Dinosaurs have been extinct sincefor over 60 million years.

9. These cherry trees have bloomed every spring sincefor 1980.

10. They have been raising horses and cows on their farm sincefor many years.