Some hard-working students always keep a torch in their dormitories _____ there is a power failure． ...
2022-10-20 23:14:51 29次 2015年湖南省怀化市高三模拟考试英语试卷（解析版） 单项填空 反馈错误 加入收藏 正确率 : 100%
题目内容：
Some hard-working students always keep a torch in their dormitories _____ there is a power failure．
A． if B． unless
C． so that D． in case
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