液体动压轴承是指运转时（）的滑动轴承。
A.半干摩擦
B.纯液体摩擦
C.混合摩擦
参考答案：B
Do you mind ________the door for me? __________
A．me to open/ Certainly
B．my closing/ Yes, please don’t.
C．me to close/ Of course not
D．my opening/ Certainly not
什么是黄土？简述黄土的一般特征？
