Yesterday our chemistry teacher teacher asked so difficult a question ( )puzzled all of us.Yesterday our chemistry teacher teacher asked so difficult a question _____puzzled all of us.Yesterday our chemistry teacher asked so difficult a question ________ it puzzled all of us.分别填什么?为什么?
问题描述：
Yesterday our chemistry teacher teacher asked so difficult a question ( )puzzled all of us.
Yesterday our chemistry teacher teacher asked so difficult a question _____puzzled all of us.
Yesterday our chemistry teacher asked so difficult a question ________ it puzzled all of us.
分别填什么?为什么?
答