首页
登录
职称英语
Not all sounds made by animals serve as language, and we have only to turn t
Not all sounds made by animals serve as language, and we have only to turn t
游客
2024-02-15
41
管理
问题
Not all sounds made by animals serve as language, and we have only to turn to that extraordinary discovery of echolocation (回声定位) in bats to see a case in which the voice plays a strictly practical 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 near a wall or a mountainside, an echo will come back. The further off this solid obstacle, the longer time it will take for the return of the echo. A sound made by tapping on the main body 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 equipment, 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 equipment, it is now possible not only to locate fish but to tell if it is herring, cod, or other well-known fish, by the pattern of its echo.
A few years ago it was found that certain bats emit squeaks (吱吱声) and by receiving the echoes they could locate and steer clear of obstacles—or locate flying insects on which they feed. This echolocation in bats is often compared with radar, the principle of which is similar. [br] The main purpose of this passage is to ______.
选项
A、describe that animals can make different sounds
B、prove that animals’ voices can play practical roles
C、inspire the readers to make more inventions
D、startle the readers with some shocking facts
答案
B
解析
主旨大意题。文章第1段就点明主题,明确指出以蝙蝠为例,动物发出的声音有实际作用,只有B可以概括文章的这个写作目的。
转载请注明原文地址:https://tihaiku.com/zcyy/3454283.html
相关试题推荐
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
TheWebWaytoLearnaLanguageTheyoungwomanseatedne
Languagelearningbeginswithlistening.Individualchildrenvarygreatlyin
Languagelearningbeginswithlistening.Individualchildrenvarygreatlyin
【S1】[br]【S8】O本句是拿Achildtaughtasecondlanguageafterageten和a______作比较,并
【S1】[br]【S4】DasecondlanguageaffordstostudentssuchasRola实际是一个省略了关系代词的定语
随机试题
ComeSeptember,thecampusesofAmericawillbeswarmingnotjustwithretu
Inrecentdecades,franchising(专卖店)hasgrownincreasinglypopularandwide
HenryFieldingistheauthorofA、TheHistoryofTomJones,aFoundling.B、Robins
[audioFiles]audio_eufm_j01_190(200910)[/audioFiles]A、Paintingtheroomwhite.B
人寿保险不丧失价值条款规定,投保人处置失效保单现金价值的方式有()。A.重新
下列行为可以构成犯罪的是( )。A.参加传销组织 B.多次敲诈勒索他人财物
下列关于胎漏的叙述中不正确的是A.下腹酸坠、疼痛 B.阴道出血 C.查尿hC
使用无菌容器,操作正确的是()。A.盖的内面朝下,以便放置稳妥 B.物品取出
编制城市规划这一行为属于行政行为中的()。A.具体行政行为 B.抽象行政
下列机构中,不属于中国银行保险监督管理委员会负责监管的非银行金融机构是( )。
最新回复
(
0
)