分类：教育/科学-外语学习-英语考试
问题：一道单选题Idon’tthinkhecouldhavedones 
I don’t think he could have done sh a stupid thing last night ,_________?A. do I        B. could he        C. did he           D. has he 
回答：I don’t think he could have done sh a stupid thing last night ,____C_____? A. do I B. could he C. did he D. has he 这道题没有多少需要思考的余地,不过要注意与第三人称的he thinks对比.I think 可以看作插入语,同意楼上的关于废话的理解,确实是,对自己无须反义疑问.补充:但是第三人称就不行了,因为说的不是自己的话,所以要用does/did +主语.此题属于I think 是不起作用的情况,所以对后面的内容进行反义疑问,即对he could have done进行反义疑问.could have done是说过去本来就会做的事情,could have done 表示假设， 与过去的事实相反。 如：He could have been very rich, but he cared for no money at all. 即对过去的虚拟的事实进行反义疑问,用did+主语.综上选C.