型钢及管材的装载高度超出侧墙(板)时,每垛货物至少安插()。
参考答案:2对支柱
Look and answer.
1. What's the matter, Jack?
2. What's the matter, Helen?
3. How heavy are you?
4. Are you taller than your sister?
木地面的构造方式不包括()。
A.架空
B.实铺
C.悬挂
D.粘贴