注：1.第二句Thanks to sonar... 结果句
2.get along 生活 get along with 相处 3.blind 蒙住眼睛
4.We know from... 结果句 5.末句为细节
16. According to the author, the sonar system of bats is an example of the idea that ____.
A) this is the age of technological triumphs
B) modern machines are inefficient
C) living mechanisms are often more efficient than man -made machines
D) artificial imitations are always less efficient than living mechanisms
注：1.第一段 illustration 等同 example
2.D选项的always与文章中的often含义是不同的。
In these days of technological triumphs, it is well to remind ourselves from time to time that living mechanisms are often incomparably more efficient than their artificial imitations. There is no better illustration of this idea than the sonar (声纳) system of bats. It is billions of times more efficient and more sensitive than the radars and sonars designed by man.
17. The author suggests that the sonar system of bats ____
A) was at the height of its perfection 50 million years ago
B) is better than man-made sonar because it has had 50 million years to be be refined
C) should have been discovered by man many years ago
D) is the same as it was 50 million years ago
注：B 选项体现一段结尾和二段开头，应该优选，含有关系词 because,although,not only...but also, as well as 的应该优选
18. Echo location in this article means the _____.
A) location of echoes
B) ability to determine where an echo comes from
C) scientific term for sound waves
D) ability to locate unseen objects by echoes
注：1.A 为干扰选项，过于表面化
2.B 项为等价选项所以为错误
To appreciate the precision of the bats' echo location, we must first consider the degree of their reliance upon it. Thanks to sonar, an insect-eating bat can get along perfectly well without eyesight. This was brilliantly demonstrated by the Italian naturalist
Lazzaro Spallanzani. He caught some bats in a bell tower, blinded them and released them outdoors. Four of these blind bats were recaptured after they had found their ways back to the bell tower, and on examining their stomachs' contents, Spallanxani found that they had been able to capture and eat flying insects. We know from experiments that bats easily find insects in the dark of night, even when the insects make no sound that can be heard by human ears. A bat will catch hundreds of softbodied silent flying insects in a single hour. It will even detect and chase pebbles (卵石) tossed (向上扔)into the air.
19. This article was written to illustrate ____.
A) the deficiencies of man-made sonar
B) the dependence of man upon animals
C) that we are living in a machine age
D) that the sonar system of bats is remarkable
