2Choose the best answer to complete the sentences below.
1. By the end of 2009, about 100 schools ( a ) in this country.
a. was built
b. have been built
c had been building
d. had been built
2. A lot of problems ( b ) since the beginning of the meeting.
a. have discussed
b. have been discussed
C. are discussed
d. have been discussing
3. Now is the time ( ) ) we must stand together.
d. why
4. A good way to learn a foreign language is to live in a country (, ) it is spoken.
a. when
b. who
C. how
a. when
b. where
C. how
d. what