离合器由端面带有螺旋齿爪的左、右两半组成，左半部由（）带动在轴上空转，右半部分和轴上花键联结。
A、主轴
B、光杠
C、齿轮
D、花键
参考答案：B
—I forgot to bring my English book. May I use yours?
—_______. [ ]
A. I don't know
B. you can't
C. Here you are
D. No, you can ask him
过早搏动
