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
17
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] 【B3】
选项
答案
sideways
解析
空格后的and提示此处应填入表方位的副词,与backwards构成并列关系。sideways意为“斜向一边”。
转载请注明原文地址:https://tihaiku.com/zcyy/2939161.html
相关试题推荐
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
Forcenturies,farmershaveusedwindmillstopumpwater,crushgrainandpe
随机试题
MissLiudoesn’tmind__________yourhomeworkaslongasitisdonebyyourself.
[originaltext]W:I’dliketotakeatriptoFloridaformyspringbreak.Canyo
Bellshavebeenin【21】foralonglime.TheywereusedbytheChineseabout【2
Ifyou’vebeenthinkingaboutgivingupyourjob,herearetworeasonsyous
元曲的兴起对于中国民族诗歌的发展和文化的繁荣有着深远的影响。TherisingofYuanoperahasgreatinfluencesont
A.220sin(ωt+90°)V B.220sin(ωt-30°)V C.
墩台主要包括()。A.桥墩墩身 B.桥墩盖梁 C.台帽 D.耳背墙
地下洞室应尽量布置在()。A.无法避开断裂带时,地下洞室的轴线应与断裂面走向
下列关于药材浸出过程正确的是A.浸润、溶解、过滤B.浸润、溶解、解吸、过滤C.浸
若净现值为负数,表明该投资项目()。A.利润为负,不可行 B.投资报酬率
最新回复
(
0
)