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
Man has long wanted to fly. He saw birds, envied them and tried to imitate them. Over the ages, countless attempts were made: me
Man has long wanted to fly. He saw birds, envied them and tried to imitate them. Over the ages, countless attempts were made: me
admin
2008-11-28
9
问题
Man has long wanted to fly. He saw birds, envied them and tried to imitate them. Over the ages, countless attempts were made: men constructed wings, fastened them to their arms and legs and jumped off towers and hilltops. These "bird-men" flapped (拍动) their wings for a short space of time and then fell to the ground.
【B1】
What was not realized in those early years was that birds have muscles very much stronger, in proportion to their size, than men
. Human limbs cannot provide sufficient strength to lift the body off the ground.【B2】
The secret of flight did not lie in the making of wings, but in discovering the right kind of power, and how to use it.
In the 18th century, the invention of the hot-air balloon by the Montgolfier brothers of France was seen as a great step forward,【B3】
But balloons and the cigar-shaped airship, which was invented slightly later, did not solve the problem of flying because they had no means of power or control.
So the difficulty remained: a true flying machine which was heavier than air and capable of carrying people was still to be invented.【B4】
Experiments were carried out in many countries, sometimes with models driven by steam engines, but these were too heavy to be used in an airplane with a pilot.
The answer finally came at the beginning of this century with the invention of the internal combustion engine (内燃机)--the kind used in motor cars. Here at last was a powerful, yet comparatively light engine, driven by petrol and capable of being fitted into an airplane.
In 1903, two Americans, the brothers Wilbur and Orville Wright, flew a powered airplane for the first time. Their success encouraged designers everywhere.【B5】
Although there were now newer, different problems, mainly to do with safety and the training of pilots, progress was rapid.
These were exciting days and interest was intense. The age of airplane arrived.
What was not realized in those early years was that birds have muscles very much stronger, in proportion to their size, than men.
选项
答案
先前人们没有意识到的是:相对于自身的体积来说,鸟类拥有比人类强壮得多的肌肉。
解析
转载请注明原文地址:https://jikaoti.com/ti/O3hMFFFM
本试题收录于:
浙江省大学英语三级题库大学英语三级分类
0
浙江省大学英语三级
大学英语三级
相关试题推荐
Whydoestheglobalfundstopsupportinganynewprogrammes?
Whyisitsaidthattheeconomyishealthywith20millionunemployed?
WhichofthefollowingisanAmericannewspaper?
WhatwasthenameoftheshipthatbroughtthePilgrimstoNewEnglandin1620?
Beinganexperiencedinventor,Jacksonknew______allhismoneyinariskyventure.
PierreOmidyar,thesonofFrench-Iranianimmigrants,wasalreadyamillionairebeforehelaunchedeBay.Omidyar’selectronicss
It’shandytohaveaweek—thosesevendaysandsevennights—becauseitmeanswecanplanwhattodooncertaindays,andhaveor
Mostworksofartarekeptindoors,inagallery,privatehome,officebuilding,ormuseum.Onecategoryofartwork,fashionedt
Mr.Smithisbookingatourforaladyandhimselfatatravelagency.
Inradioandtelevision______impossibletodrawthelinebetweennewsandentertainmentprograms.
随机试题
流动资产管理的核心就是如何使资金加快_______。
在定义语句中,指针变量名前必须有“_________”号。
关于过碘酸-雪夫反应的染色反应叙述错误的是
下列除哪项外,均是泄泻与痢疾的鉴别要点( )。
A.饮片品种单一而数量多,库房面积小的B.大宗药材或饮片量较大C.中药或炮制品品种数量多,库房面积大的D.细料、贵重中药或饮片E.各种霉菌、害虫繁殖生长旺季宜采用仓库密封法贮存的是()
证券发行规模达到一定数量的,可以由2家以上的保荐机构联合保荐。( )
公开募集基金的基金管理人将其固有财产或他人财产混同于基金财产从事证券投资会导致()。Ⅰ.违背基金财产独立性原则Ⅱ.使基金财产与基金管理人的固有财产混淆不清Ⅲ.基金财产可以得到更多的收益Ⅳ.会对基金份额持有人的利益造成损害
中国艺术品市场近几年来一直呈现火爆态势,“天价”拍品不绝于耳。对此,中国国家文物鉴定委员会委员指出,当下中国书画拍卖市场出现的所谓“天价拍品”,很多都是出于炒作,真正的成交价让人生疑,中国书画拍卖市场存在“虚假繁荣”现象。以下除了哪项,其
货币政策.是指中央银行为实现既定的经济目标运用各种工具调节货币供给和利率,进而影响宏观经济的方针和措施的总和。主要的货币政策措施有:控制货币发行;控制和调节对政府的贷款;推行公开市场业务;改变存款准备金率;调整再贴现率;选择性信用管制;直接信用管制。根据
设随机变量X服从参数为λ的指数分布,令Y=,求:P{X+Y=0}。
最新回复
(
0
)