OG 16, SC 67题求解答···

惠荟

97. Some anthropologists believe that the genetic homogeneity evident in the world's people is the result of a "population bottleneck"—at some time in the past our ancestors suffered an event, greatly reducing their numbers and thus our genetic variation.

(A) at some time in the past our ancestors suffered an event, greatly reducing their numbers

(B) that at some time in the past our ancestors suffered an event that greatly reduced their numbers
(C) that some time in the past our ancestors suffered an event so that their numbers were greatly reduced,
(D) some time in the past our ancestors suffered an event from which their numbers were greatly reduced
(E) some time in the past, that our ancestors suffered an event so as to reduce their numbers greatly,
破折号在这里是什么功能？还有，一般看到破折号要如何处理，有破折号在，没看出来考平行

OG解释说破折号后边的部分作为believe 后从句的解释，我想问为什么破折号后的句子不能作为“population bottleneck”的解释？？？
求助啊···实在是不理解啊

咖啡印象

个人觉得破折号是作用来解释说明用的，后面跟着同位语从句，对破折号前面的句子进行解释。

adsdsd

这个帖子的解释不错
http://forum.chasedream.com/thread-835634-1-1.html

典座

adsdsd 发表于 2016-8-7 03:24
这个帖子的解释不错
http://forum.chasedream.com/thread-835634-1-1.html

谢啦谢啦