HELP!!****大家帮忙看一下这道题*****

The Anasazi settlements at Chaco Canyon were built on a spectacular scale with more than 75 carefully engineered structures, of up to 600 rooms each, were connected by a complex regional system of roads.

A.   with more than 75 carefully engineered structures, of up to 600 rooms each, were

B.  with more than 75 carefully engineered structures, of up to 600 rooms each,

C.   of more than 75 carefully engineered structures of up to 600 rooms, each that had been

D.   of more than 75 carefully engineered structures of up to 600 rooms and with each

E.   of more than 75 carefully engineered structures of up to 600 rooms, each had been   

答案是B, 

实在看不懂这道题, 哪个NN给讲一下吧.THX

在这里，of 和each 分别修饰什么啊？？

with more than 75 carefully engineered structures

把这个看成是插入语，然后，就是 sth. were built on a spectacular scale of up to 600 rooms each. 这里的each 修饰的是sth.也就是说每个sth,都达到了600个房间的规模。我是这么认为的。

这题曾经深深困扰我，我想好久

好心的版主已经有整理连结。

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