卧式铣床主轴承受切削力后产生让刀的最常见原因是机床主轴磨损。
参考答案:错
—Do you like sports?
—Sure. I'm looking forward to watching the 29th Olympic Games _____ in Beijing on TV. [ ]
A. to hold
B. being held
C. held
D. to be held
简述铁路罐车上部卸油系统气阻的产生原因?