起重机上三大安全构件是:() A.卷筒组、钢丝绳、吊钩 B.制动器、联轴器、主梁 C 发布时间:2019-01-08 20:13 │ 来源:www.tikuol.com 题型:单项选择题 问题: 起重机上三大安全构件是:()A.卷筒组、钢丝绳、吊钩B.制动器、联轴器、主梁C.主梁、小车架、端梁D.制动器、钢丝绳、吊钩
题型:单项选择题 —Anything I can do for you,Madam?—I’d like_______eggs and some cabbages.A.a half dozenB.a dozens ofC.half a dozen ofD.half a dozen 查看答案