求教gwd10 verbal3 一道语法题

aztheroe

For protection from the summer sun, the Mojave lived in open-sided, flat-topped dwelling known as shades, each a roof of poles and arrowweed supported by post set in a rectangle.

A each a roof of poles and arrowweed

B each a roof of poles and arrowweed that are being

C with each being a roof of poles and arrowweed

D with roofs of poles and arrowweed to be

E with roofs of poles and arrowweed that are

答案是A， 确实也是A看着最像答案，但是这题的语法点一直没有搞清楚，那位大牛能帮帮忙给讲一下，多谢多谢！

[此贴子已经被作者于2006-3-20 2:35:18编辑过]

yaoyao99

My guess is C, D and E implies that the "shades" are something else, a tent for example, with roofs of poles and arrowweed as an additional feature, similar to "a room with lots of color" or "a cake with lots of frosting."