圆形翻车机由旋转笼体,传动装置()传动轮、支持轮、旋转定位器、操纵装置、挡矿板、机座、阻车器等主要部分组成。
参考答案:液压和机械
在管涵施工时,无企口的管节接头采用( ),应尽量顶紧,缝宽不得大于10mm,严禁因涵身长度不够,将所有接缝宽度加大来凑合涵身长度。
A.贴墙接缝
B.四周接缝
C.顶身接缝
D.顶头接缝
—Mary broke up with me!
—You _____ have forgotten about the Valentine's Day.
A.shouldn't
B.couldn't
C.needn't
D.mustn't