首页
登录
职称英语
For centuries men dreamed of achieving vertical flight. In 400 A.D. Chinese
For centuries men dreamed of achieving vertical flight. In 400 A.D. Chinese
游客
2023-08-19
25
管理
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. [br] 【B9】
选项
答案
multitude
解析
空格前的their other提示此处应填入名词。multitude意为“大量”,这里表示直升机的其他很多用途。
转载请注明原文地址:https://tihaiku.com/zcyy/2939167.html
相关试题推荐
[originaltext](23)Morethanhalfof500Chinesecitiesfailedtomeetnational
Forcenturiesmendreamedofachievingverticalflight.In400A.(D),Chines
Forcenturiesmendreamedofachievingverticalflight.In400A.(D),Chines
Forcenturiesmendreamedofachievingverticalflight.In400A.(D),Chines
Forcenturiesmendreamedofachievingverticalflight.In400A.(D),Chines
传统中国装饰绳结,也就是我们所说的中国结(Chineseknot),是一种典型的中国本土艺术。这是一门独特的传统中国民间手工编织艺术,每个绳结只使用一
中医(traditionalChinesemedicine)起源于6000多年前的神农氏时代,这位著名的中国古代药王所生活的时代被认为是中医史上的
在上海、北京、南京、广州等许多城市中,穿着唐装(traditionalChinesegarment)的时髦女子成为一道美丽的风景线。传统唐装做工细致
传统中国装饰绳结,也就是我们所说的中国结(Chineseknot),是一种典型的中国本土艺术。这是一门独特的传统中国民间手工编织艺术,每个绳结只使用一
[originaltext]Today,ChineseAmericansmakeuplessthan1%oftheU.S.pop
随机试题
Heresented______towait.Heexpectedtheminister______himatonce.A、tobeask
Thelecturewasmuchmoredifficult______(比我预期的).thanIhadexpected①than表示“比,比较
Dafterinterviewingbecomecommonpractice【S1】______intheUnite
[originaltext](20)Scientistswhostudytheearthtellusthatthecontinen
PassageOne[br]WhatarePacManandCentipede?Popularvideogames.首段第2句中PacMa
InordertorentanddriveacarinJapan,yourequireaJapanesedrivingli
如题32图所示,其总的传递函数G(s)=C(s)/R(s)为( )
A.金线吊葫芦B.金钱环C.金钱眼D.金包头E.金井玉栏俗指毛知母根茎顶端残留的
二级耐火等级的厂房,其楼梯间墙的耐火极限不应低于()h。A.2.00 B.1
关于麦芽的叙述,错误的是A.回乳可用至120g B.气虚无食积痰滞者慎服 C
最新回复
(
0
)