The rocket engine, with its steady roar like that of a waterfall or a thunderstorm, is an impressive symbol of the new space age

admin2015-01-28  15

问题     The rocket engine, with its steady roar like that of a waterfall or a thunderstorm, is an impressive symbol of the new space age. Rocket engines have【C1】______powerful enough to shoot astronauts【C2】______the earth’s gravitational pull and【C3】______them on the moon. We have now become【C4】______in space. Yuri Gagarin from Soviet Union was the first human to visit space on April 12, 1961. In the 108 minutes’ journey, he covered 40, 000 kilometers. China’s first astronaut into space is Yang Liwei. Impressive and complex【C5】______it may appear, the rocket, which was【C6】______in China over 800 years【C7】______, is a relatively simple device. Fuel that is【C8】______in the rocket engine changes【C9】______gas. The hot and rapidly【C10】______gas must escape, but it can do so only【C11】______an opening that【C12】______backward. As the gas is【C13】______with great force, it【C14】______the rocket in the【C15】______direction. Like the kick of a gun【C16】______it is fired, it【C17】______the laws of nature【C18】______by Sir Isaac Newton when he discovered that "【C19】______every action, there is【C20】______equal and opposite reaction. " Newton’s theories have contributed a great deal to the science of aeronautics.
【C8】

选项 A、round
B、contained
C、stored
D、burned

答案D

解析 由后面的The hot and rapidly. 35gas…可推知,只有被燃烧了,才会有热气体产生。所以句意为“火箭引擎里燃烧的燃料”,burned正确。
转载请注明原文地址:https://kaotiyun.com/show/hejd777K
0

最新回复(0)