多层悬挑式按落地式脚手架的要求搭设。（）
参考答案：对
we___________last night,but we went to the concert instead.
A．must have studied
B．might study
C．should have studied
D．would study
汇管的作用是将天然气汇集后，再根据实际情况进行（）。
A.分输
B.储存
C.分离除尘
D.控制
