1 . She brought her three friends to the party, none of ________I had ever met before. (用适当的词填空)

2 . The number of smokers, _________ is reported, has dropped by 17 percent in just one year. （用适当的词填空）

3 . In 1963 the UN set up the World Food Program, one of_________purposes is to relieve worldwide starvation.（用适当的词填空）

4 . Dr. Rowan, ________ secretary resigned (辞职) two weeks ago, has had to do all his own typing.（用适当的词填空）

5 . ________ is often the case, we have worked out the production plan.

6 . A lot of language learning, _________ has been discovered, is happening in the first year of life, so parents should talk much to their children during that period.（用适当的单词填空）

7 . There are many forms of communication,______include text message, cellphones,emails, and so on. (用适当的单词填空)

8 . There are about 100 teachers, two-thirds of______are women. (用适当的单词填空)

9 . Zhong Nanshan, ________ you all know, is a well-known medical expert in China.

A．which

B．who

C．as

D．because

10 . It is his fourth visit in a month, ________ says it all.

A．who

B．that

C．which

D．where