1 . He promised that he ________ (buy) some gifts for us when he ________ (get) there. (所给词的适当形式填空）

2 . Her husband died because of smoking last month and she ________(ban) her son from smoking ever since. (所给词的适当形式填空)

3 . She sang very well.I've never heard a _____ (beautiful) voice. （所给单词适当形式填空）

4 . A TV can be a real ______(bless) for old people. （所给单词适当形式填空）

5 . Humankind should avoid such a war as could result in the use of chemical and ________ (biology) weapons. （所给词的适当形式填空）

6 . I couldn’t afford __________(buy) these books, so I borrowed them from the library.

7 . That day I went up to speak to him, __________ he turned away and left.

8 . China is a country which ________ (belong) to the third world.

9 . It is about time that we __________ (ban) over-fishing to preserve the ecological balance.

10 . Jim fell asleep in the math class today. That is ___________ he stayed up until midnight doing his homework.