Since или for. Урок английского языка

1. We have received no news sincefor 5:30 pm.

2. We've been friends with Fred sincefor decades.

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

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

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

6. Jane has worked here sincefor two weeks already.

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

8. He worked at that company sincefor ten years before he retired.

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

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