1. I've known my best friend _for 15 years.
a) for
b) since
2. __since ___ last Christmas, I haven't eaten any chocolate.
a)for
b)since
3. He's been sick __since ___ the last week.
a)for
b)since
4. Bob's worked there __since___ 1984.
a) for
b) since
5. I've been telling you to hurry up __for___ the last 30 minutes!
a)for
b)since
6. My mother has been trying to call me __since___ last week.
a) for
b) since
7. They have been colleagues __for ___ a long time.
a)for
b)since
8. He has been studying Russian ___for __ a few months.
a) for
b)since
9. I haven't seen her __since ___ last year.
a)for
b) since
10. I've been angry at him __since___ a couple of weeks ago.
a) for
b)since
Объяснение:
