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
2024-04-14
42
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] 【B6】
选项
答案
strategic
解析
此处需要名词、形容词或分词作定语,修饰名词instruments。strategic意为“战略的”。
转载请注明原文地址:https://tihaiku.com/zcyy/3555426.html
相关试题推荐
[originaltext]Today,ChineseAmericansmakeuplessthan1%oftheU.S.pop
[originaltext]Today,ChineseAmericansmakeuplessthan1%oftheU.S.pop
JustlikeChinese,Westernersgivegiftsonmanyoccasions,suchas,onbirt
JustlikeChinese,Westernersgivegiftsonmanyoccasions,suchas,onbirt
JustlikeChinese,Westernersgivegiftsonmanyoccasions,suchas,onbirt
Forcenturiesmendreamedofachievingverticalflight.In400A.D.Chinese
Forcenturiesmendreamedofachievingverticalflight.In400A.D.Chinese
Forcenturiesmendreamedofachievingverticalflight.In400A.D.Chinese
Forcenturiesmendreamedofachievingverticalflight.In400A.D.Chinese
Forcenturiesmendreamedofachievingverticalflight.In400A.D.Chinese
随机试题
Whatistherecommendedstockofcoal?[br]Whatdoesthewomanwanttodoabout
Itisappropriateonananniversaryofthefoundingofauniversitytoremin
Thebusmovedslowlyinthethickfog.Asaresult,wearrivedatour______almos
Sowhatisbullyingintheworkplace?Accordingtotheexperts,ittakesman
OnFoodSafety,aLongListbutLittleMoneyA)Thissummer
男性患者,20岁,14天前始出现发热,体温38~39℃,无寒战,伴右侧胸痛,轻度
A.L-抗坏血酸 B.盐酸硫胺 C.核黄素 D.盐酸吡多辛 E.氰钴胺维
规范,是指人们在特定环境下被要求如何行动、如何思维、如何体验的期望,是一种相对固
2014年,国务院发布了《国家新型城镇化规划(2014--2020年)》,下列内
用最大短路电流校验导体和电器的动稳定,热稳定时,应选取被效验导体和电器通过最大短
最新回复
(
0
)