Since или for. Урок английского языка

1. You haven't smoked sincefor two months.

2. I haven't slept sincefor 48 hours.

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

4. Jane has worked here sincefor two weeks already.

5. He's been working in the field sincefor early this morning.

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

7. John and Bob have been working on this project sincefor five months already.

8. New ideas have been put into practice sincefor he was elected our leader.

9. They've been teaching here sincefor quite a long time.

10. Joe and Josephine have been going out together sincefor Valentine's Day.