885-sec3-23 canon shooting

givemeahome

23.    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) that shoots dead chickens at airplanes has proved helpful in demonstrating

A 为何错

friday

名词+现在分词作定语：意思是“总是。。。”
名词+that 从句作定语，意思是：“在具体时间。。。”
in doing ........... 在某一方面

may1129

'has proved ' doesn't have a comparable time period.
additionally, 'the cannon is helpful' is a fact that won't change overtime, therefore, 'proves' is preferred.

personal opinon only

麻集爱

为什么用完成时？？？  谁能告诉我？？？

谢谢

zwt8564

up

gonghao

奇怪，同问A的问题。

分词修饰不是做总是解释吧

why A is wrong？

elaineyin819

现在分词表示一个重复性的动作,强调的动作或过程，在一个笼统的时间下进行

定语从句表示一次性动作，强调结果或状态,是在具体时间/情况下发生的

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

不能说一个大炮一直在射击死鸡吧？！这里应该是一个一次性的动作，而且这个动作发生在为了说明/解释当飞机飞入鸟群所带来的破坏这个特定的场景下。因此在这里应该用定语从句

sameoldstory

如果E改成:that shoots dead chickens at airplanes has proved helpful to demonstrat可以吗?

zoutongguang

姐，E就是答案好不好

jeffjarrett

如果E改成:that shoots dead chickens at airplanes has proved helpful to demonstrat可以吗?

-- by 会员 sameoldstory (2007/9/15 16:28:00)

我可以很不负责任的说helpful in demonstrating是固定搭配吗？