铣削铝合金时硬质合金铣刀通常选用铣削速度是（）m/min。
A.50~100
B.400~600
C.800~100
参考答案：B
His father demands that he not go to any country _________ China, which is his motherland.
A．rather than
B．more than
C．other than
D．better than
润滑系在使用和维护过程中应注意些什么？
