高速旋转机械大多采用()。
A.滚动轴承
B.高精度滚动轴承
C.非液体摩擦润滑滑动轴承
D.液体摩擦润滑滑动轴承
参考答案:D
163. _____ you are leaving tomorrow, we can eat dinner together tonight.
A.For
B.Now that
C.When
D.While
空调病