数控机床机械系统的日常维护中,须每天检查的部件是()
A.导轨润滑油
B.液压油路
C.滚珠丝杠
D.润滑液压泵
参考答案:A
I like the music that I can sing ______.[ ]
A. along and
B. along with
C. with
D. along
国际收支平衡表是按照()原理编制的。