首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
What’s the main topic of this passage?
What’s the main topic of this passage?
admin
2018-04-19
63
问题
What’s the main topic of this passage?
Before a new plane goes into service, every part of it is tested again and again. But there are two tests that are more important than all the others. In the first test, a modern airliner must fly at very high altitudes. Air must be pushed into the airliner so that the passengers can breathe. The metal structure of the plane has to be very strong for this reason. When the airliner is filled with air, the air presses against the skin of the plane inside. The pressure on a small window, for instance, is like a huge, giant foot that is trying to get out. If a small part of the plane were to crack, the plane would explode in the sky. It is lowered into a huge tank of water to test the structrue of the plane. Then it is filled with air. The pressure inside the plane is greater than it ever will be when it is in the air. Finally, there is an explosion. Engineers can discover which part of the plane has cracked.
In the second test, the test pilot must find out exactly what happens when all the engines are shut off at once. He takes the plane up very high. Then he shuts the engines off, the plane begins to fall like a stone. It is the pilot’s job to find out how he can control the plane again. These two tests are examples of how planes are made safe before they ever carry passengers.
选项
A、Because without air the plane can’t fly.
B、Because the plane needs air for its fuel.
C、Because the passengers’ lives depend on air.
D、Because the passengers have paid for it.
答案
C
解析
转载请注明原文地址:https://kaotiyun.com/show/lMRd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
Whatcanbeinferredfromthisspeech?
HowmanyzonesistheLondonundergroundnetworkdividedinto?
Governmentsthroughouttheworldactontheassumptionthatthewelfareoftheirpeopledependslargelyontheeconomicstrength
Itishardtotrackthebluewhale,theocean’slargestcreaturewhichhasalmostbeenkilledoffbycommercialwhalingandisn
Thetangohasprobablytraveledfurtherandgonethroughmorechangesthanalmost【21】______.Africanslavesbroughtthetan
Thetangohasprobablytraveledfurtherandgonethroughmorechangesthanalmost【21】______.Africanslavesbroughtthetan
Thetangohasprobablytraveledfurtherandgonethroughmorechangesthanalmost【21】______.Africanslavesbroughtthetan
Sincethe【21】______oftheNationalEnvironmentalPoliciesActin1969,theUnitedStatesCongress,legislatureatthefede
Applecomputerintroduceditspioneering,user-friendlyMackintoshcomputerin1984.The"Mac"quicklybecamepopularandappeare
WouldyouliketoorbittheEarthinsidetheInternationalSpaceStation?Nowyoucantakeaspaceholiday—forapriceThisis
随机试题
下列各项中,属于产品成本项目中制造费用包括的内容有()。
下列著作约成书于战国时代的是()
A、左归丸B、右归丸C、加减一阴煎D、血府逐瘀汤E、苍附导痰丸治疗闭经阴虚血燥证,应首选
A、退热除蒸B、凉血止血C、软坚散结D、明目,润肠E、祛痰,益气墨旱莲除滋阴益肾外,又能()。
(2009、2008)下列电气设备,哪个不应在高层建筑内的变电所装设?
企业所得税的纳税人为对外投资而借入的资金所发生的借款费用,可以计入纳税人的经营性费用在税前扣除。( )
甲公司从事建材生产作业,其在外地设有一分公司乙,并且已取得营业执照;2016年8月,因生产规模扩大,乙公司决定新招一批生产工人。随后乙公司在当地招聘了包括小王和小李在内的15名工人,9月1日开始工作。乙公司与应聘个人口头约定了工作内容和工资数额。
Sorry,Iamtoobusynow.IfI______time,Iwouldcertainlygoforanoutingwithyou.
组织、领导传销活动罪中“传销活动”的特征包括()
Anine-year-oldschoolgirlsingle-handedlycooksupascience-fairexperimentthatendsupdebunkingawidelypracticedmedical
最新回复
(
0
)