【单选题】His father began to work ______his childhood.
【判断题】艺术的价值更多地体现在“艺术附加值”上。
【单选题】8名患者的体重(kg) 分别为: 51、45、46、52、58、51、57、70,其中位数为( )
【单选题】Tom went to open the door. ______, his father began to wash dishes. [ ]
【简答题】各种表面加工方法所能达到的精度和()都有一个相当大的范围。
【单选题】His father began to work ______ his childhood.
【判断题】数控机床伺服系统主要有两种:一种是进给伺服系统,它控制机床各坐标轴的切削进给运动,以直线运动为主;另一种是主轴伺服系统,它控制主轴的切削运动,以旋转运动为主。( )