Look! The ground is wet. It must have rained last night, ？
A. hasn't it
B. hadn't it
C. mustn't it
D. didn't it
网友回答
A. hasn't it
B. hadn't it
C. mustn't it
(答案→)D. didn't it
解析：D 考查反意疑问句。句意：看！地是湿的。昨晚一定下过雨，是不是？It must have rained last night是推测语气，可改写为I think it rained last night，可见其反意疑问部分应为didn't it，故选D项。