Question 22——32

　　　　Crows are probably the most frequently met and easily identifiable members of the

　　native fauna of the United States . The great number of tales, legends, and myths about

　　these birds indicates that people have been exceptionally interested in them for a long

　　time. On the other hand, when it comes to substantive —— particularly behavioral ——

　　information, crows are less well known than many comparably common species and,

　　for that matter, not a few quite uncommon ones: the endangered California condor, to

　　cite one obvious example. There are practical reasons for this.

　　　　 Crows are notoriously poor and aggravating subjects for field research. Keen

　　observers and quick learners, they are astute about the intentions of other creatures,

　　including researchers, and adept at avoiding them. Because they are so numerous,

　　active, and monochromatic, it is difficult to distinguish one crow from another. Bands,

　　radio transmitters, or other identifying devices can be attached to them , but this of

　　course requires catching live crows, who are among the wariest and most untrappable

　　of birds.

　�。牐� Technical difficulties aside , crow research is daunting because the ways of these

　　birds are so complex and various. As preeminent is generalists, members of this species ingeniously exploit a great range of habitats and resources, and they can quickly adjust

　　to changes in their circumstances. Being so educable, individual birds have markedly

　　different interests and inclinations, strategies and scams.

　　For example, one pet crow

　　learned how to let a dog out of its kennel by pulling the pin on the door. When the dog

　　escaped, the bird went into the kennel and ate its food.

　　22.What is the main topic of the passage?

　　(A) The ways in which crows differ from other common birds

　　(B) The myths and legends about crows

　　(C) The characteristics that make crows difficult to study

　　(D) The existing methods for investigating crow behavior

　　23. According to the first paragraph, what evidence is there that crows have interested people for a long time?

　　(A) The large number of stories about crows.

　　(B) The frequency with which crows are sighted

　　(C) The amount of research that has been conducted on crows

　　(D) The ease with which crows are identified

　　24. The word "comparable" in line 5 is closest in meaning to

　　(A) interestingly

　　(B) similar

　　(C) otherwise

　　(D) sometimes

　　25. In line 6, the author mention the endangered California condor as an example of a species that is

　　(A) smaller than the crow

　　(B) easily identifiable

　　(C) featured in legends

　　(D) very rare

　　26. In line 6, the author mentions the endangered California condor as an example of a species that is

　　(A) crows

　　(B) subjects

　　(C) intentions

　　(D) researchers

　　27.According to the second paragraph, crows are poor subjects for field research for all of the following reasons EXCEPT

　　(A) They can successfully avoid observers.

　　(B) They are hard to distinguish from one another

　　(C) They can be quite aggressive.

　　(D) They are difficult to catch.