— Susan, go and join your sister cleaning the yard.

— Why ___? John is sitting there doing nothing.

A．him

B．he

C．I

D．me

墙体的结构布置方案主要有（）。

A.横墙承重

B.纵墙承重

C.纵、横墙混合承重

D.部分框架承重

E.剪力墙承重