[求助]大全854

854.        There is ample evidence, derived from the lore of traditional folk medicine, that naturally occurring antibiotics are usually able to be modified to make them a more effective drug.

(A) are usually able to be modified to make them a more effective drug.

(B) are usually able to be modified to make them more effective drugs

(C) are usually able to be modified, which makes them more effective drugs

(D) can usually be modified to make them a more effective drug

(E) can usually be modified to make them more effective drugs

E

请教各位ｎｎ，be able to be done是否在什么情况下都是错的呢？据说新东方上课的时候就是这么说的，在题目中也反复看到有这个结构的选项都被枪毙了，大家怎么看呢？

为什么我自己在题目后面打的字显示不出来呢？好奇怪哦

请教各位ｎｎ，是否be able to be done在任何情况下都是不对的？据说新东方老师上课的时候是这么说的，大家怎么看呢？

谢拉

记得有位NN说过be able to be done乃兵家大忌

只能说98%的情况下这条是适用的,我见到过例外,但是一下子实在找不道是哪道题了...

谢谢各位拉：）