M20×1.5中,1.5表示()为1.5mm。
A.螺距;
B.导程;
C.线数;
D.直径;
参考答案:D
The great chance he has been looking forward to _______ at last.
A.appear
B.appearing
C.has appeared
D.appeared
在“日键关,坐便坐”中,“键”之义为()
A.关门
B.门轴
C.户抠
D.门槛