В первом предложении не are а is
<span>Many new towns
are being built in Siberia and in the Far East.Some of the towns were
founded about 20 years ago.The first costruction teams were organized in
1959 when the Moscow University physics students decided to spend their
summer vacations working at construction projects.Since that time a lot
of dwellings have been built by the students of different
institutes. Many students were awarded orders and medals for their work
during the "third semester".</span>
1 We have travelled to lots of countries.
2 Mrs. Green has worked in the office for 25 years. And she is still working.
3 she rang her boss yesterday.
4 The lecture hasn't begun yet and the students are talking in the classroom.
5 I haven't seen him since 1987.
1. was shining, cycled
2. came, was getting
3. was carrying, saw
4. was still reading, rang
5. was looking, went
6. didn't know, prefered
7. was practicing, didn't hear
8. was heaving, arrived
9. didn't know, loved
10. was still living, died
11. was dancing, saw, stopped
12. was ringing, was dressing
13. was always going
14. там точно такое предложение было?
15. saw, was going