第1篇 Researchers Discover Why Humans Began Walking Upright
31. Which NOT A Many people question the simple human activities of walking and carrying items.
32. Dr. Richmond conducted the experiment with the purpose of finding B What made our ancestors walk upright.
33. Kyoto,Universitry’s study discovered that chimpanzees C liked coula nuts better than oil palm nuts.
34. Why did the chimpanzees walk on two limbs during Kyoto University's experiment? D Because they wanted to carry more nuts with two free limbs.
35. What can we infer from the reading passage? D Human walking on two legs developed as a means of survival.
第2篇 Ants Have Big Impact on Environment as "Ecosystem Engineers"
36 .Why are ants compared to ecosystem engineers?
C Because their activity affects the environment.
37. As predators, ants
A prey on small as well as large animals.
38. Dir Sanders' study centered on how ants
D produce such a big impact on the environment.
39. What does paragraph 6 tell us?
B Ants bring about a positive influence to an area when their population is small.
40. What still remains unclear about ants, according to the last paragraph?
C How do human activities affect ants' influence on a given ecosystem?