Question

He must have learn English for three years,___? A.hasn't he B.haven't he C.mustn't he D.didn't he

网上有这种说法：陈述部分有must 的疑问句，疑问部分根据实际情况而定。
He must be a doctor, isn't he?
You must have studied English for three years, haven't you? / didn't you?
He must have finished it yesterday, didn't he?
那这道题A和D都对吗？请详细讲解此题。

Answer 1

1.must 表示推测时，其后的反意疑问句要根据must后的谓语动词一致。
你查到的几个句子有两个对，中间那个不对。
You must have studied English for three years, haven't you? / didn't you?
这个句子只能用haven't , 不可以用didn't.
2.在前面的陈述句中有具体的过去的时间状语时才用didn't 。所以第三个句子是正确的。
He must have finished it yesterday, didn't he?
那么你的单选题：He must have learn English for three years,___?
A.hasn't he B.haven't he C.mustn't he D.didn't he
正确答案就是A。

如果有疑问就hi我。祝你学习愉快！

Answer 2

1.must 表示推测时，其后的反意疑问句要根据must后的谓语动词一致。
你查到的几个句子有两个对，中间那个不对。
You must have studied English for three years, haven't you? / didn't you?
这个句子只能用haven't , 不可以用didn't.
2.在前面的陈述句中有具体的过去的时间状语时才用didn't 。所以第三个句子是正确的。
He must have finished it yesterday, didn't he?
那么你的单选题：He must have learn English for three years,___?
A.hasn't he B.haven't he C.mustn't he D.didn't he
正确答案就是A。

我相信我的理解，也祝你学习进步！

Answer 3

我觉得是A。
首先 hasn't 是与前面的have 是对应的，时态应该一致 ；一般mustn‘t只用于禁止的意思。
从时态一致来说应该前后对应，
不过如果是你们单元题目的话，可能考得是你们刚刚学的内容。

Answer 4

我认为是：选c，用什么问，用什么大。

这是我的理解，希望能帮到你！