returns?

21. What do we know about the fly in Book 1?___________

A. She is brave and ambitious. B. She is stupid but interesting.

C. She is loyal and courageous. D. She is honest but stubborn.

22. What can we learn from the text?____________

A. Book 4 is the cheapest of the four books.

B. Both Book 2 and Book 3 contain many pictures.

C. The fly in Book1enjoys staying with her siblings.

D. The head teacher in Book 2 thinks highly of the kid.

23. The books mentioned above are intended for .

A. parents B. children C. animal lovers D. architects

　　For most city people, the elevator is an unremarkable machine that inspires none of the enthusiasm or interest that Americans afford trains, jets, and even bicycles. Dr. Christopher Wilk is a member of a small group of elevator experts who consider this a misunderstanding. Without the elevator, they point out, there could be no downtown skyscrapers or tall buildings, and city life as we know it would be impossible. In that sense, they argue, the elevator's role in American history has been no less significant than that of cars. In fact, according to Wilk, the car and the elevator have been locked in a "secret war" for over a century, with cars making it possible for people to spread horizontally(水平地), and elevators pushing them toward life in close groups of towering vertical (垂直的) columns.

　　If we tend to ignore the significance of elevators, it might be because riding in them tends to be such a brief, boring, and even awkward experience one that can involve unexpectedly meeting people with whom we have nothing in common, and an unpleasant awareness of the fact that we're hanging from a cable in a long passage.

　　In a new book, Lifted, German journalist and cultural studies professor Andreas Bernard directed all his attention to this experience, studying the origins of elevator and its relationship to humankind and finding that riding in an elevator has never been a totally comfortable experience. "After 150 years, we are still not used to it, "Bernard said. "We still have not exactly learned to cope with the mixture of closeness and displeasure." That mixture, according to Bernard, sets the elevator ride apart from just about every other situation we find ourselves in as we go about our lives.

　　Today, as the world's urban population explodes, and cities become more crowded, taller, and more crowded, America's total number of elevators-900,000 at last count, according to Elevator World magazine's "2012 Vertical Transportation Industry"-are a force that's becoming more important than ever. And for the people who really, really love them, it seems like high time that we looked seriously at just what kind of force they are.

24. What does the underlined word "this" in Paragraph 1 refer to?

A. The particular interests of experts._________

B. The general view of elevators.

C. The desire for a remarkable machine.

D. The enthusiasm for transport vehicles.

25. The author's purpose in mentioning cars is .

A. to emphasize the importance of elevators B. to contrast their functions with elevators

C. to reveal their secret war against elevators D. to explain people's preference for elevators

26. According to Prof. Bernard, what has made the elevator ride different from other life experiences?__________

A. Vertical direction. B. Little physical space.

C. Lack of excitement. D. Uncomfortable conditions.

27. The author urges readers to consider. ___________