must have 的反问疑问

问题描述:

must have 的反问疑问
You must have left your bag in the theatre,haven't you?你一定是把包落在剧场了,是不是?Aunt Liu must have got to the U.S.A.yesterday,didn't she?刘大婶昨天准是到了美国了,对不?两句话,前面同样是 must have为什么一个是haven't you
didn't she
怎么分辨

当must+have done表示对过去的情况进行推测(一般句中有明确的过去时间状语),问句要根据陈述部分谓语的情况用“didn't+主语”或“wasn't/weren't+主语”;如果强调动作的完成(一般没有明确的过去时间状语),问句要用“haven't/hasn't+主语”.
She must have read the novel last week,didn't she?
她上星期一定读了这本小说,是吗?
You must have told her about it,haven't you?
你一定把这事告诉她了,是吗?