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
For centuries men dreamed of achieving vertical flight. In 400 A.D. Chinese children played with a fan-like toy that spun upward
For centuries men dreamed of achieving vertical flight. In 400 A.D. Chinese children played with a fan-like toy that spun upward
admin
2016-04-03
45
问题
For centuries men dreamed of achieving vertical flight. In 400 A.D. Chinese children played with a fan-like toy that spun upwards and fell back to earth as rotation ceased. Leonardo da Vinci conceive the first mechanical【B1】______, called a "Helix," which could carry man straight up, but was only a design and was never tested.
The ancient-dream was finally realized in 1940 when a Russian engineer piloted a strange looking craft of steel tubing with a rotating fan【B2】______. It rose awkwardly and vertically into the air from a standing start, hovered a few feet above the ground, went 【B3】______ and backwards, and then settled back to earth. The vehicle was called a helicopter.
Imaginations were fired. Men dreamed of going to work in their own personal helicopters. People anticipated that vertical flight transports would carry millions of passengers as do the airliners of today. Such fantastic expectations were not【B4】______.
The helicopter has now become an extremely useful machine. It【B5】______ in military missions, carrying troops, guns and【B6】______ instruments where other aircraft cannot go. Corporations use them as airborne offices, many metropolitan areas use them in police work, construction and logging companies employ them in various【B7】______ ways, engineers use them for site selection and surveying, and oil companies use them as the best way to make offshore and remote work stations【B8】______ crews and supplies. Any urgent mission to a hard-to-get-to place is a likely task for a helicopter. Among their other 【B9】______ of use: deliver people across town, fly to and from airports, 【B10】______ rescue work, and aid in the search for missing or wanted persons.
【B5】
选项
答案
excels
解析
空格所在句子缺少谓语,根据主语it和前后文的语态,推断此处应填入动词第三人称单数形式。excel意为“擅长”。
转载请注明原文地址:https://kaotiyun.com/show/0zG7777K
0
大学英语六级
相关试题推荐
Itmayseemridiculous,butinthehuntforsourcesofalternativeenergyresearchershavecomeupwithfuelcellswhicharepow
Breedinginmostorganismsoccursduringapartoftheyearonly,andsoareliablecueisneededtotriggerbreedingbehaviour.
AccompanyingIndia’sindustrialtransformationhasbeenanotherrevolutionofprofoundsignificance.Aproperty-owningmiddlecl
A、Theywanttostayhomeanddothehousework.B、Theydonothaveenoughmoney.C、Theyhavetoomuchworkandnotmuchfreetime
A、Thewomanexpectsthemantomakeanimportantdecision.B、Theman’sfatherisaverysuccessfulbanker.C、Theyarebothmakin
Businessesarestructuredindifferentwaystomeetdifferentneeds.The【B1】______formofbusinessiscalledanindividualpropr
HighSchoolSportsAren’tKillingAcademics[A]Inthismonth’sAtlanticcoverarticle,"TheCaseAgainstHigh-SchoolSports."Am
经过多年的摸索,绿色交通的发展理念早已成为我国交通运输行业发展的共识。根据规划,到2020年,我国交通运输行业有关指标将比2005年实现大幅提升,基本建成绿色循环低碳交通运输体系。要实现这一目标,加快智能交通系统(intelligenttransport
A、Someonealreadyborrowedhernewspaper.B、She’llgetthenewspaperbackfromthemanlater.C、Shecan’tlendthemanthenewsp
随机试题
在文件的逻辑组织中,不属于记录文件的是()。
此时进行X线检查首选的片位是出现上述情况后,术后用药应首选
《刑事诉讼法》规定,审判的时候被告人不满18周岁的案件,不公开审理。但是,经未成年被告人及其法定代理人同意,未成年被告人所在学校和未成年人保护组织可以派代表到场。关于该规定的理解,下列哪些说法是错误的?(2012年卷二第73题)
下列说法中正确的有()。
[*]
()被称为武器装备的“心脏”,是现代军事技术的核心和基础,广泛应用于雷达、计算机、通信设备、导航设备、火控系统、制导设备和电子对抗设备等各类军用设备上。
《人民警察法》第二十条规定,人民警察职业道德方面的义务有()。
公安机关督察机构设督察长,由()担任。
已知矩阵相似于对角矩阵用正交变换化二次型f(x)=XTBX为标准形,其中X=(x1,x2,x3)T为3维向量。
以下不能输出小写字母a的选项是
最新回复
(
0
)