I don’t think he has finished his work yet, _________?（反义疑问句）

答案是；has he
反意疑问句中，陈述部分是宾语从句，主句的主语是第一人称，谓语是think,suppose,believe,suspect,imagine等时，其疑问部分与宾语从句相对应构成反意疑问句。如：
I think he is right,isn't he?
若主语不是第一人称，其疑问部分与主句相对应构成反意疑问句。如：
He thought they were wrong,didn't he?
否定前置时，如：I don't think he is right,is he? 陈述部分相当于 I think he is not right 所以，疑问部分用肯定结构，是 is he?

本题中，首先主句是第一人称，谓语动词是think，所以，疑问部分与从句相对应；从句是现在完成时，疑问部分要用现在完成时的助动词has提问；又由于是否定前置，相当于陈述部分是否定，所以疑问部分是肯定。因此，答案是：has he？

希望对您有所帮助！

这类的问题实际上是
否定前置。
可以变形为 i think he hasn't finished his work yet。因为主语是第一人称。所以前面的不变变后面的。
所以答案应该是 has he?

如果是第三人称作主语的话。
例。
he doesn't think she has finished her work yet,-------
因为是第三人称。所以是对主语提问。
所以就是
he doesn't think she has finished her work yet ,does he?

hasnt him

hasn't he?