机床主轴的回转误差分为()、纯径向跳动和纯角度跳动三种。
参考答案:轴向窜动
I had wanted to clean out the basement ______, but unfortunately he came back before I did it. [ ]
A. in a hurry
B. in his absence
C. in his memory
D. in his company
被习 * * * * 喻为“鸟之两翼,车之两轮”的是()。
A.和平和发展
B.独立和自主
C.改革和法治
D.创新和创业