物料提升机的组成中,起到提升天梁作用的工作机构是()。
A.架体
B.吊笼
C.自升平台
D.卷扬机
参考答案:C
解析:自升平台是架体安装加高和拆卸的工作机构,起到提升天梁的作用。
He was a bit nervous. He _________his spare breath with a soft sound that was almost heard by the audience.
A.gave out
B.let out
C.picked out
D.blew out.
下列体现矛盾特殊性原理的是
A.因地制宜
B.好钢用在刀刃上
C.一把钥匙开一把锁
D.牵牛要牵牛鼻子