《新概念英语》第四册 Lesson 7 Bats

Lesson 7 Bats

First listen and then answer the following question.

In what way does echo-location in bats play an utilitarian role?

Not all sounds made by animals serve as language, and we have only to turn to that extraordinary discovery of echo-location in bats to see a case in which the voice plays a strictly utilitarian role.

To get a full appreciation of what this means we must turn first to some recent human inventions. Everyone knows that if he shouts in the vicinity of a wall or a mountainside, an echo will come back. The further off this solid obstruction, the longer time will elapse for the return of the echo. A sound made by tapping on the hull of a ship will be reflected from the sea bottom, and by measuring the time interval between the taps and the receipt of the echoes, the depth of the sea at that point can be calculated. So was born the echo-sounding apparatus, now in general use in ships. Every solid object will reflect a sound, varying according to the size and nature of the object. A shoal of fish will do this. So it is a comparatively simple step from locating the sea bottom to locating a shoal of fish. With experience, and with improved apparatus, it is now possible not only to locate a shoal but to tell if it is herring, cod, or other well-known fish, by the pattern of its echo.

It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles -- or locate flying insects on which they feed. This echo-location in bats is often compared with radar, the principle of which is similar.

MAURICE BURTON Curiosities of animal life

New words and expressions

生词和短语

bat  n.  蝙蝠

In China bats are thought of as being very lucky 

在中国，蝙蝠被视为吉祥物。

了解字母B的象形意义（点击以下链接）：

cod  [kɑːd]  n.  鳕鱼

strictly  [ˈstrɪktli]  adv. 明确地

strict + ly 副词后缀

strict [strɪkt]  adj.严格的(指必须恪守);严厉的;恪守教规(或信条等)的

She was brought up very strictly.

她从小家教很严。

utilitarian [ˌjuːtɪlɪˈteriən]  adj.实用的

utilit〔y〕公用事业；有用 + arian …的 → 有用为主 → 功利主义的

Bruce's office is a corner one, utilitarian and unglamorous.

布鲁斯的办公室在角落里，实用而普通。

appreciation [əˌpriːʃiˈeɪʃn]  n.  理解

appreciate + ion 名词后缀

appreciate [əˈpriːʃieɪt]  v.欣赏;赏识;重视;感激;感谢;欢迎;理解;意识到;领会

ap 表加强 + prec 价值 +i + ate 动词后缀 →〔因为欣赏〕反复评价 → 评价；欣赏

Please accept this gift in appreciation of all you've done for us.

承蒙鼎力相助，不胜感激，谨备薄礼，敬请笑纳。

elapse [ɪˈlæps]   v.  障碍物

e 向外 + laps 滑，滑走 + e → 滑走 →〔时光〕流逝

Many years elapsed before they met again.

过了许多年他们才再次相见。

hull  [hʌl]  n.  船体

同源词：hall，cell。

They climbed onto the upturned hull and waited to be rescued.

他们爬上了倾覆的船体，等候救援。

interval  [ˈɪntərvl] n.  间隔

inter 在中间 + val (词源同wall)， 原指两堵墙之间的空间，后引申为间隔，间歇。

The interval between major earthquakes might be 200 years.

大地震之间的间隔时间可能有200年。

receipt  [rɪˈsiːt] n.  收据;收条;接收;收到;(企业、银行、政府等)收到的款项，收入

re 再，又 + ceipt （=cept）拿，取

Are you in receipt of any state benefits?

你目前是否享有政府补助金？

apparatus  [ˌæpəˈrætəs]  n.  仪器

ap 加强 + para 准备 + tus 名词后缀 → 准备好用的东西 → 设备

Firefighters needed breathing apparatus to enter the burning house.

消防队员需要呼吸器以便进入燃烧的大楼。

shoal  [ʃoʊl]  n.  鱼群

同源词：school

The shark described a circle around the shoal of fish. 

这条鲨鱼围绕着鱼群游动。

herring  [ˈherɪŋ]  n. 鲱鱼(产于北大西洋，成大群游动，可食)

同源词：hoar，因这种鱼灰白色的颜色而得名。

fresh herring fillets

新鲜鲱鱼片

pickled herrings

腌制的鲱鱼

squeak [skwiːk]  n.  尖叫声 

The mouse ran away, squeaking with fear.

那只老鼠吓得尖叫着溜了。

参考译文

动物发出的声音不都是用作语言交际。我们只要看一看蝙蝠回声定位这一极不寻常的发现，就可以探究一下声音在什么情况下有绝对的实用价值。

要透彻理解这句话的意义，我们应先回顾一下人类最近的几项发明。大家都知道，在墙壁或山腰附近发出的喊声，就会听到回声。固体障碍物越远。回声返回所用时间就越长。敲打船体所发了的声音会从海底传回来，测出回声间隔的时间，便可算出该处海洋的深度。这样就产生了目前各种船舶上普遍应用的回声探测仪。任何固体者反射声音，反射的声音因物体的大小和性质的不同而不同。鱼群也反射声音。从测定海深到测定鱼群，这一进展比较容易。根据经验和改进了的仪器，不仅能够确定鱼群的位置，而且可以根据鱼群回声的特点分辨出是鲱鱼、鳕鱼，这是人们所熟悉的其他鱼。

人们发现，某些蝙蝠能发出尖叫声，并能通过回声来确定并躲开障碍物，或找到它们赖以为生的昆虫。蝙蝠这种回声定位常常可与雷达相比较，其原理是相似的。

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