3.The letter is from my sister, ______is working in Beijing.

A. which B. that C. whom D. who

4.I lost a book, ______I can't remember now.

A. whose title B. its title C. the title of it D. the title of that

5.This machine, ______for many years, is still working perfectly.

A. after which I have looked B. which I have looked after

C. that I have looked after D. I have looked after

Key: 1-5 BDDAB

巩固提高

1.He is working hard, ______will make him pass the final exam.

A.that B.which C.for which D.who

2.I have two grammars, ______are of great use.

A. all of which B. either of which C. both of that D. both of which

3. Smoking, _______ is a bad habit, is, however, popular.

A. that B. which C. it D. though

4. I shall never forget those years when I lived on the farm with the farmers, _______ has a great effect on my life.

A. who B. which C. that D. which

5. Have you ever listened to the song Yesterday once more, _______ singer died in her early years?

A. its B.it's C. whose D. which

6. John got beaten in the game, _______ had been expected.

A. as B. that C. what D. who

7. I have bought two ballpens, _______ writes well.

A. none of them B. neither of them

C. neither of which D. none of which

8. To get the job started, _________ I need is your permission.

A. only what B. all what C. all that D. only that

9. My father bought me several books, but _________ was interesting.

A. most of them B. none of them C. none of which D. neither of which

10. Liu Xiang's breaking the world record was an exciting moment, _________ all of us will never forget.

A. that B. one C. it D. what

Key: 6-10BDBA 10-15 ACCCD

1. The foreign guests, _________ were scientists, were warmly welcomed at the airport.

A. most of whom B. most of them C. most of