21.　 Egypt is a country _____ is famous for its pyramids.

A. where　　 B. which　　　 C. in which　 　D. at which

20.　 It is the factory _____ his father wanted to go to.

A. that　　 B. the one　　 C. where　　 D. what

19.　 It is the factory _____ his father worked a few years ago.

A. that　　 B. which　　 C. where　　 D. what

18.　 Is this the university _____ you visited last time?

A. that one　　 B. which　　 C. the one　　 D. the one what

17.　 Is this college _____ they went to last year?

A. that　　 B. which　　 C. the one　　 D. the one what

16.　 Is the river _____ through the town very long?

A. flows　　 B. that flows　　 C. which flow　　 D. the one flows

15.　 On the train I saw a student _____ I thought was your sister.

A. who　　 B. whom　　 C. which　　 D. that

14.　 I can still remember the sitting-room ____ my mother and I used to sit in the evening.

A. what　　 　B. which　　 C. that　　　 D. where

13.　 The foreign guests, _____ were scientists, were warmly welcomed at the airport.

A. most of whom　 B. most of them　 C. most of which　 D. most of those

12.　 All _____ is needed is a supply of oil.

A. the thing　　　 B. that　　 C. what　　 D. which