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Lesson 7 Bats 蝙蝠

发布者: 雪狼 | 发布时间: 2006-11-13 10:25| 查看数: 12943| 评论数: 0|



英音版录音



美音版录音



First listen and then answer the following question.

听录音,然后回答以下问题。

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(1.2)[bæt] n.蝙蝠

interval(1.6)['intəvəl]n.间隔

strictly(1.2)['strikti] adv.明确地

receipt(1.7)[ri'si:t] n.收到

utilitarian(1.2)[ˌju:tiliˈtɛəriən] adj.实用的

apparatus(1.8)[ˌæpəˈreitəs] n.仪器

appreciation(1.3)[əˌpri:ʃiˈeiʃən] n.理解

shoal(1.9)[ʃəul] n.鱼群

obstruction(1.5)[əbˈstrʌkʃən] n.障碍物

herring(1.11)['heriŋ] n.鲱鱼

elapse(1.5)[i'læps] v.消逝

cod(1.11)[kɔd] n.鳕鱼

hull(1.6)[hɔl] n.船体

squeak(1.13)[skwi:k] n.尖叫声

Notes on the text课文注释

1Not all sounds made by animals serve as language,动物发出的声音不全是作语言交际。此句采用了部分否定,即不是否定所有的动物,而只是一部分。serve as,作……之用。

2turn to,求助于。

3play a role in,在……方面起作用。

4in the vicinity of,在……的附近。

5So was born the echo-sounding apparatus,这样就诞生了回声探测仪。这是一个倒装句,主要是为了避免因主语过长而使全句失去平衡,同时也为了使apparatus的定语now in general use in ships 紧挨着名词。in general use,普遍使用。

6steer clear of,避开。

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。敲打船体所发出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。任何固体都反射声音,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,还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。蝙蝠的这种回声定位常常可与雷达相比较,其原理是相似的。

Comprehension理解

Give short answers to these questions in your own words as far as possible.Use one complete sentence for each answer.

1How is the echo-location principle applied to measure the depth of the sea?

2Why do the sounds reflected by solid objects vary?

3What use do bats make of the principle of echo-location?

Vocabulary词汇

Refer to the text to see how the following words have been used, then write sentences of your own using these words: strictly utilitarian (1.2); vicinity (1.4); elapse (1.5); tapping (1.5); apparatus (1.8); shoal (1.9); comparatively (1.9); emit (1.13); steer clear (11.13-14).

Sentence structure句子结构

ACombine the following sentences to make one complex statement out of each group.Make any changes you think necessary, but do not alter the sense of the original.Refer to the passage when you have finished the exercise:

1Not all sounds made by animals serve as language.We have only to turn to that extraordinary discovery of echolocation in bats.We can see a case in which the voice plays a strictly utilitarian role.(11.1-2)

2A sound can be made by tapping on the hull of ship.It will be reflected from the sea bottom.We can measure the time interval between the taps and the receipt of the echoes.The depth of the sea at that point can be calculated.(11.5-7)

3Every solid object will reflect a sound.This varies according to the size and nature of the object.(11.8-9)

4With experience, and with improved apparatus, it is now possible to locate a shoal.It is possible to tell if it is herring, cod, or other well-known fish, by the pattern of its echo.(11.10-12)

5A few years ago it was found that certain bats emit squeaks.

They received echoes.They could locate obstacles.

They could stear clear of obstacles.They could locate flying insects on which they fed.(11.13-14)

BWithout referring to the passage write three sentences indicating three different uses of the principle ofecho - location.

Key structures关键句型

ACompare these two sentences:

Instead of saying: If we wish to get a full appreciation of what this means we must turn first to some recent human inventions.

We can say: To get a full appreciation of what this means we must turn first to some recent human inventions.(1.3)

Complete the following sentences:

1To understand ______.

2To enjoy ______.

3To succeed _____.

BSupply a, an, or the where necessary in the following paragraph.Do not refer to the passage until you have finished the exercise:

Everyone knows that if he shouts in _____ vicinity of ______ wall or ________ mountainside, ___ echo will come back.______ further off this solid obstruction, ______ longer time will elapse for ___ return of ______ echo._______ sound made by tapping on _____ hull of _____ ship will be reflected from ________ sea bottom, and by measuring _______ time interval between ________ taps and _______ receipt of ______ echoes _______ depth of _______ sea at that point can be calculated.Sowas born _______ echo - sounding apparatus, now in _____ general use in ______ ships.Every solid object will reflect ______ sound, varying according to _____ size and _____ nature of _____ object._______ shoal of _______ fish will do this.So it is ________ comparatively simple step from locating ________ sea bottom to locating ______ shoal of _______ fish.(11.3-10)

CStudy the form of the verbs in italics in these sentences:

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.(11.5-7) It has been found that certain bats emit squeaks and by receiving the echoes they can locate … obstacles.(11.13-14) Write three sentences in the same way using by followed by the -ing form of a verb.

DNote that the verb compared is followed by with in this sentence: Echo-location in bats is … compared with radar … (11.14-15)

Supply with, for, or to in the following sentences:

1I have been corresponding _____ him for many years.

2He was arrested and charged ______ murder.

3How much do you charge _______ this service?

4I can't provide you ________ all the things you need.

5We have provided _____ every emergency.

6Did you apply ________ that job?

7If you want a loan you should apply ______ the bank.

8He's much too quick for me.I just can't compete ______ him.

Special difficulties难点

AStudy the following pairs of words and then write sentences of your own to bring out the difference.

1sound (1.1) ---- echo (1.2)

Don't make a sound, any of you!

The echo of the gunfire died away, and the valley was quiet again.

2discovery (1.1) ---- invention (1.3)

The discovery of oil in Alaska was a boon to the economy.

The invention of personal computers was a very important event in the second half of the twentieth century.

3appreciation (1.3) ---- estimation

He lacks a realistic appreciation of the situation.

In my estimation, you'll need twelve rolls of wallpaper.

4obstruction (1.5) ---- obstacle (1.14)

There's an obstruction in the fuel pipe.

Fear of change is the greatest single obstacle to progress.

5steer (1.13) ---- drive

The captain steered his ship into the harbour.

It's quite possible to drive from Geneva to London in a day.

BSupply the missing words in these sentences:

1Not all the sounds made _______ animals serve as language.(1.1)

2This camera was made _________ Japan.

3Glass is made ____ sand and lime.

4This watch is made____ gold.

CExplain the word experience in these sentences:

1With experience it is now possible not only to locate a shoal but to tell if it is herring, cod, or other well-known fish.(11.10-11)

2He is a very experienced surgeon.

3It was one of the strangest experiences I have ever had.

DWhat does the phrase to tell if mean in this sentence:

It is now possible to tell if it is herring, cod, or other well-known fish.(11.10-11)

Write two sentences using to tell if.

ENote the spelling of echoes(1.12).Write the plural of the following words: potato, piano, tomato, solo.

Multiple choice questions多项选择题

Choose the correct answers to the following questions.

Comprehension 理解

1What happens if you shout on a mountainside?

a.You will be able to measure distance.

b.Nothing.

c.It will take a long time for an echo to come back.

d.You will hear an echo.

2You can measure the depth of the sea by ____.

a.shouting so you get back an echo

b.tapping on the hull of a ship

c.working out how long it takes to get an echo from the sea bottom

d.calculating the reflection

3The echo-location principle means you can even ____.

a.locate and distinguish different species of fish

b.hear a fish's echo

c.improve the apparatus now in use

d.easily catch different species of fish

4Bats use echo-location to ____.

a.see where they're going

b.avoid bumping into things

c.avoid flying insects

d.emit squeaks

Structure句型

5Not ____sound made by animals serves as language.(l.1)

a.every

b.each

c.the whole

d.the entire

6We have only to turn to that extraordinary discovery of echo-location in bats to see a case ____the voice plays a strictly utilitarian role.(11.1-2)

a.which

b.where

c.when

d.why

7____ he shout in the vicinity of a wall, an echo will come back.(1.4)

a.Should

b.If

c.When

d.Though

8____ the echo-sounding apparatus was born.(11.7-8)

a.Such

b.The way

c.That's how

d.Like this

Vocabulary词汇

9The voice plays a strictly ____ role.(1.2)

a.secondary

b.important

c.usual

d.practical

10A sound made by ____ the hull of a ship - (11.5-6)

a.hitting

b.knocking

c.beating

d.bashing

11The sound varies ____the size and nature of the object.(11.8-9)

a.depending on

b.relating to

c.influencing

d.by

12A ____ of fish will do this.(1.9)

a.class

b.herd

c.school

d.flock



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