________, it began to rain unexpectedly. A. While cleaning the machine B. To clean the machine C. He...
2022-12-26 18:49:56 118次 2015届甘肃永昌县第一高级中学高一上学期期中考试英语试卷（解析版） 单项填空 反馈错误 加入收藏 正确率 : 100%
题目内容：
________,
it began to rain unexpectedly.
A. While
cleaning the machine
B. To
clean the machine
C. He
was cleaning the machine
D. While
he was cleaning the machine
本题链接：
