For centuries man dreamed of achieving vertical flight. Leonardo da Vinci co

游客2024-02-06  21

问题     For centuries man dreamed of achieving vertical flight. Leonardo da Vinci conceived the first mechanical apparatus(仪器), which could carry a man【C1】______up, but this was only a design and was never tested.
    The ancient dream was finally realized in 1940 when a Russian aeronautical(航空学的)【C2】______, piloted a strange-looking craft of steel tubing with a rotating fan on top. It rose awkwardly and vertically into the air from a standing start, hovered a few feet above the ground, went sideways and backwards, and then settled back to earth. That【C3】______was called a helicopter.
    Imaginations were fired. People【C4】______that vertical flight transports would carry millions of passengers as do the airliners of today. Such fantastic expectations were not【C5】______. It excels in military missions,【C6】______troops, guns and strategic instruments where other aircraft cannot go. Corporations use them as airborne offices; many urban areas use them in police work, construction and logging companies【C7】______them in various advantageous 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 accessible to crews and supplies. Any urgent【C8】______to a hard-to-get-to place is a likely task for a helicopter. Among their other【C9】______of uses, they deliver people across town, fly to and from airports,【C10】______in rescue work, and aid in the search for missing or wanted persons. With all these functions, the helicopter has now become an extremely versatile machine.
A)recognize B)vehicle C)caustic D)anticipated
E)actually F)fulfilled G)employ H)carrying
I)mission J)straight K)helpless L)engineer
M)assist N)balancing O)abundance [br] 【C9】

选项

答案 O

解析 这里需要名词,后面的内容是对他们用途的举例,根据前文可知,直升机有多种用途,故推测这里是说它的用途广泛,故选abundance。
转载请注明原文地址:https://tihaiku.com/zcyy/3426527.html
最新回复(0)