首页
登录
职称英语
The great advance【C1】______rocket theory 40 years ago showed that liquid-fue
The great advance【C1】______rocket theory 40 years ago showed that liquid-fue
游客
2025-01-22
25
管理
问题
The great advance【C1】______rocket theory 40 years ago showed that liquid-fuel rockets were far【C2】______in every respect to the skyrocket with its weak solid fuel, the only kind of rocket then known.【C3】______, during the last decade, large solid-fuel rockets with【C4】______fuels about as powerful as liquid fuels have【C5】______their appearance, and it is a favorite layperson’s question to【C6】______which one is "better". The question is meaningless.【C7】______might as well ask whether a gasoline or a diesel engine is "better". It all【C8】______on the purpose. A liquid-fuel rocket is complicated,【C9】______has the advantage that it can be controlled beautifully. The burning of the rocket engine can be stopped completely; it can be reignited when【C10】______.【C11】______, the thrust can be made to vary by adjusting the speed of the fuel pumps. A solid-fuel rocket, on the other hand, is rather【C12】______in construction,【C13】______hard to build when a really【C14】______size is desired. But once you have a solid-fuel rocket, it is ready for action【C15】______very short notice. A liquid-fuel rocket has to be fueled first and cannot be【C16】______readiness for very long after it has been fueled.【C17】______, once a solid-fuel rocket has been ignited, it will keep burning. It cannot be stopped and reignited【C18】______desired(it could conceivably be stopped and reignited after a pre-calculated time of burning has e-lapsed. and its thrust cannot be varied. Because a solid-fuel rocket can be kept ready for a long time, most military missiles【C19】______solid fuels, but human-piloted spaceflight needs the fine adjustments that can【C20】______be provided by liquid fuels. [br] 【C3】
选项
A、However
B、Therefore
C、But
D、On the contrary
答案
A
解析
前后句意转折,可选However和But,但But后不能加逗号,所以选However。
转载请注明原文地址:https://tihaiku.com/zcyy/3923276.html
相关试题推荐
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
Thegreatadvance【C1】______rockettheory40yearsagoshowedthatliquid-fue
随机试题
Wherehasthewomanbeen?[originaltext]M:It’sgoodtoseeyouback.Howwasyo
Pretendingtobehappycanactuallymakeyoumore【B1】______—especiallyify
Thecompanyhadtoputforwarda(propose)______thatlay-offs(下岗)beconsidered
()riskscannotbemanagementproactively
诊断性电视胸腔镜手术的适应证中,不包括A.纵隔肿瘤 B.胸部外伤 C.胸膜疾
患者,男,60岁。呛咳少痰,气短自汗,口干舌燥,苔薄少津,脉虚细。治疗应首选A.
A.补火助阳,温通经脉B.温中回阳,温肺化饮C.散寒止痛,疏肝下气D.温中降逆,
引起小儿麻痹症最常见的病毒是()。A.脊髓灰质炎病毒 B.柯萨奇病毒
某地下一层服装商场建筑面积1000m2,设有室内消火栓和自动喷水灭火系统保护,
下列关于税务行政复议管辖的说法中,不正确的有()。A.对税务所(分局)、各级税
最新回复
(
0
)