21. The lawyer questioned the witness about ______.
A. what knew he B. what did he know
C. he knew D. what he knew
22. By 2003 my hometown had become ______ industrial city in the province.
A. one of the three largest B. a third largest
C. the third largest D. the three largest
23. The concept ______ to describe the way nations behave，but it is equally applicable to individuals.
A. is most often used B. most often use
C. is often most used D. is most used often
24. Japanese scientists do not know for sure ______ Mount Fuji will erupt again.
A. where B. that
C. when D. which
25. It’s not good laughing ______ other people’s shortcomings.
A. with B. on
C. about D. at
26. An object is said ______ if its temperature is much higher than that of our bodies.
A. to be hot B. as being hot
C. hot D. as hot
27. After that quarrel，Sam didn’t talk to Paul ______.
A. any more B. no more
C. much longer D. no longer
28. It allows advertisers to combine sight，sound and motion，thus ______ to almost all the viewers’senses.
A. appeal B. and appeals
C. appealing D. appeals
29. If it ______ tomorrow，we’ll have to stay indoors.
A. would rain B. will rain
C. rained D. rains
30. He ______ the Chinese Volunteers Army in 1951.
A. joined B. had joined
C. has joined D. has been joined
