gwd1-19

kingdoms

Q19:

Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.

 

1. not caused by stress, alcohol, or rich foods, but
2. not caused by stress, alcohol, or rich foods, but are by
3. caused not by stress, alcohol, or rich foods, but by
4. caused not by stress, alcohol, and rich foods, but
5. caused not by stress, alcohol, and rich foods, but are by

这道题答案是C, 哪位nn讲讲为什么by不可省略? 为什么not要在caused 的后面?

多谢.

yogaII

平行结构：

not by x, but by y

Shadowx

最好的方法:

A not B but C 的句型

AB 需成立

AC 也需成立

這裡

Recently physicians have determined that stomach ulcers are caused (A) by stress, alcohol, or rich foods (B).

Recently physicians have determined that stomach ulcers are caused (A) by a bacterium that dwells in the mucous lining of the stomach.(C).

選別的你可以試試看 AC 都不太會成立

kingdoms

感谢,yogaII, Shadowx, 两位老兄的指点, Shadowx的方法真不错.

Thanks a lot.