什么是剖视图？
参考答案：
假想用剖切面剖开机件，把处在观察者和剖切面之间的部分移去，将其余部分向投影面投影所得的图形称为剖视图。
请你用所给单词的适当形式填空。
1.Teenagers should ________ to choose their own clothes. (allow)
2.I think it's wrong to get our ears _________ when we are at school. (pierce)
3.Have you made a ________ to buy an MP4? (decide)
4.You must pay attention to your _________. (pronounce)
5.I am very ________ of my head teacher. (terrify)
电缆的接地芯线必须与电气设备、电缆连接装置接地线柱可靠连接。（）
