装配图中实心件被剖切平面通过其对称平面或轴线纵向剖切时，这些零件按（）绘制。
A.全剖
B.半剖
C.局剖
D.不剖
参考答案：D
To test which food was better for a long space journey, the astronauts in Shenzhou VII had as many
as 50 dishes ____. [ ]
A. to choose
B. to be chosen
C. to choose from
D. to be chosen from
如果电动机六极引出线接错一相，会产生什么现象？
