求助 GWD6-2

cjmizi

Q2:

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

1. each a roof of poles and arrowweed
   
2. each a roof of poles and arrowweed that are being
   
3. with each being a roof of poles and arrowweed
   
4. with roofs of poles and arrowweed to be
   
5. with roofs of poles and arrowweed that are
   

请问each a roof of poles and arrowweed supported by posts set in a rectangle 是什么意思?

cx_ding

每一个有棍子和arrow草组成的屋顶，由搭成长方形的柱子支撑。