大全551

viviansecret

551.        Once positioned in space, the Hubble Space Telescope will capture light from sources twenty times fainter compared to those that can be detected by ground-based instruments.

(A) compared to those that can be detected

(B) compared to those they can detect

(C) than that can be detected

(D) than those that can be detected

(E) than those detecting

答案：D。请问下D选项中those后面的that可不可以被省略？

飞鹰_JK

因为有can，所以必须是：than those that can be detected by

如果没有can,那么就是than those detected by就可以，这是可以省略that,

than those can detected by 是不可以的

viviansecret

我明白了，在没有can的情况下，than those (that are) detected by是成立的，因为同时省略了that are。但是有can就不可以省略that了，否则后面定语从句结构不完整了。呵呵，多谢指教：）

[此贴子已经被作者于2009/8/19 11:55:27编辑过]

windcorner

请问those 是指代sourcs吗？谢谢

viviansecret

对的，就是指代sources的！

[此贴子已经被作者于2009/8/19 23:47:11编辑过]