Some anthropologists believe that the genetic homogeneity evident in the world’s people is the result of a "population bottleneck" - some time in the past our ancestors suffered an event from which their numbers were greatly reduced and thus our genetic variation.
语法 Sentence Correction-15394
标记
正确的用户笔记
WDSLMR 2015-06-24 02:02:27
Some anthropologists believe that the genetic homogeneity evident in the world’s people is the result of a “population bottleneck” - (they believe) that at some time in the past our ancestors suffered an event that greatly reduced their numbers and thus our genetic variation. anthropologists是破折号前后的主语，括号中的是可以利用平行格式省略的。但是必须加that，不加的话ancestors就变成后面的主语了
香蕉小姐 2015-05-03 15:55:18
reduce后面跟两个宾语－numbers和genetic variation。因此这里reduce不能用被动。
siasiasia 2016-04-09 13:56:25
and前后不平行；
fu4 2016-10-06 21:40:06
需要at some time
yhhzj110 2016-09-04 00:17:13
that的需要重复以表示平行 要么at some time可以当状语 要么sometime当状语
托福必胜！！！ 2016-06-02 09:01:17
some time前面必须要加at，才能表示时间状语。and前后也不平行
Egoyiyy 2016-03-05 15:36:29
some time前面必须要加at，才能表示时间状语。and前后也不平行
yjylain 2016-01-01 15:19:31
some time 一段时间 at some time 在一段时间。
时光老人 2015-12-29 12:42:12
some time是名词性短语，不能充当状语。应该加上at介词短语
ypheroin 2015-12-04 21:40:34
some time前面必须要加at，才能表示时间状语。
lyf0420 2015-11-28 22:31:00
语法--at some time in the past --sometime in the past...在没有介词的情况下用和写的sometimes
彩色的你 2015-11-25 12:32:38
意思为from event our ancestors suffered their numbers were greatly reduced.
