Protective clothing must be worn when the machine is in _________. A. order B. operation C. line D. ...
2022-08-24 21:29:36 98次 新疆兵团第二师华山中学2018-2019学年高二下学期第一次调研英语试卷 单项填空 反馈错误 加入收藏 正确率 : 100%
题目内容：
Protective clothing must be worn when the machine is in _________.
A. order B. operation
C. line D. public
本题链接：
