电动锚机中的带式制动器用来（）
①刹住链轮；
②控制松链速度；
③固定锚链。
A.①②
B.②③
C.①③
D.③
参考答案：A
I don't think she is a nice woman; I am _____ her empty talk.[ ]
A. grateful for
B. tired of
C. crazy about
D. concerned about
如何理解礼仪的规范性原则？
