大全055

schine

According to United States Air Force officials, a cannon shooting dead chickens at airplanes has proved helpful to demonstrate what kind of damage can result when jets fly into a flock of large birds.

(A) shooting dead chickens at airplanes has proved helpful to demonstrate

(B) shooting dead chickens at airplanes has proved itself helpful as a demonstration of

(C) shooting dead chickens at airplanes proves itself helpful as demonstrating

(D) that shoots dead chickens at airplanes proves itself helpful to demonstrate(E)

(E) that shoots dead chickens at airplanes has proved helpful in demonstrating

I chose A, but the answer is E. If E is chosen, it becomes "A cannon has proved helpful in ....". However, I have thought that the event "a cannon shooting the dead chicken" is the subject.

steve66

1.helpful in doing应该是主要考点；

2.即使选择A也是cannon proved...

none123

为什么是has proved，为什么不用被动语态，不应该是被证明吗？如果是has proved，这个句子读不通啊。。

kiwifoodtown

为什么是has proved，为什么不用被动语态，不应该是被证明吗？如果是has proved，这个句子读不通啊。。

-- by 会员 none123 (2013/3/4 10:38:03)

一件事情证明一个结论，不需用被动，因为不是它本身被证明，而是它要证明其他。

none123

明白了，谢喽！