I don't think he could have done such a stupid thing last ni
1个回答

I don't think/I think的反义疑问句,以从句为准.但是当think前边的主语是二三人称时,以think前边的主语为准.couldn‘t have done(否定前移了)表示对过去的否定推测,表推测时,不以情态动词为准.若后边有表过去的时间词(如last night),则用did提问,若没有表过去的时间词,以have提问.

所以第一题选 C;

第二题选 C.

不懂追问.