【CET 12-24备战】之六级听力（二十四）

Passage Two
14.
A) It limited their supply of food.
B) It made their eggshells too fragile¹.
C) It destroyed many of their nests.
D) It killed many baby bald eagles.

15.
A) They found ways to speed up the reproduction of bald eagles.
B) They developed new types of feed for baby bald eagles.
C) They explored new ways to hatch² baby bald eagles.
D) They brought in bald eagles from Canada.

16.
A) Pollution of the environment.
B) A new generation of pest killers⁴.
C) Over-killing by hunters.
D) Destruction of their natural homes.

答案及参考原文：

BDD

America's National Symbol – the Bald Eagle almost went extinct⁵ 20 years ago. But it has made a comeback. In fact, the US Fishing and Wildlife Service is considering the possibility of taking it off the endangered species⁶ list. Once, more than 50,000 pairs of bald eagles nested across the country. But by 1960, that number had fallen below 400. The chief killer³ was the widely used DDT. Fish soaked up DDT died and were washed up on shores where bald eagles feasted on them. DDT prevented eagle eggshells from thickening. The shell became so thin that they shattered⁷ before the babies hatched(14). Fortunately in 1972, a law was passed to ban DDT, which saved the bald eagle from total wipeout. And since then wildlife biologists have reintroduced bald eagles from Canada to America(15). The result was that last year US bird watchers counted 11,610 bald eagles in the country. If it were dropped from the endangered list, the bald eagles would still be a threatened species. That means the bird would continue to get the same protection. No hunting allowed, and no disturbing of nests. But bald eagles still face tough times. The destruction of their natural homes could be the next DDT causing eagle numbers to drop quickly(16).

14. What was the main harmful effect of the pest-killer DDT on bald eagles?
15. What measure did the wildlife biologists take to increase the number of bald eagles?
16. According to the speaker, what is the possible danger facing bald eagles?

1 fragile   

adj.易碎的，脆的，易损坏的，虚弱的，脆弱的

参考例句：

• The old lady was increasingly fragile after her operation.那位老太太手术后身体越来越虚弱。
• This glass disc looks very fragile.这个玻璃盘子看起来很容易碎。

2 hatch   

n.孵化，舱口；vt.孵，孵出，策划；vi. 孵化

参考例句：

• No one knows how the new plan will hatch out.谁也不知道这新方案将怎样制订出来。
• The bird mistook the pebble for egg and tried to hatch it.这只鸟错把卵石当蛋，想去孵它。

3 killer   

n.杀人者，杀人犯，杀手，屠杀者

参考例句：

• Heart attacks have become Britain's No.1 killer disease.心脏病已成为英国的头号致命疾病。
• The bulk of the evidence points to him as her killer.大量证据证明是他杀死她的。

4 killers   

凶手( killer的名词复数 )； 消灭…者； 致命物； 极难的事

参考例句：

• He remained steadfast in his determination to bring the killers to justice. 他要将杀人凶手绳之以法的决心一直没有动摇。
• They were professional killers who did in John. 杀死约翰的这些人是职业杀手。

5 extinct   

adj.灭绝的，不再活跃的，熄灭了的，已废弃的

参考例句：

• All hopes were extinct.所有希望都破灭了。
• Dinosaurs have been extinct for millions of years.恐龙绝种已有几百万年了。

6 species   

n.物种，种群

参考例句：

• Are we the only thinking species in the whole of creation?我们是万物中惟一有思想的物种吗？
• This species of bird now exists only in Africa.这种鸟现在只存在于非洲。

7 shattered   

破碎的； 极度疲劳的

参考例句：

• He dropped the vase and it shattered into pieces on the floor. 他失手把花瓶掉到地板上摔碎了。
• The experience left her feeling absolutely shattered. 她在这次经历之后，感到彻底垮了。