If the sky fell down,what__?A.did you think would happen B.do you think would happen.
问题描述：
If the sky fell down,what__?A.did you think would happen B.do you think would happen.
If the sky fell down,what__?
A.did you think would happen B.do you think would happen.
C.do you think will happen D.do you think will have happened.
为什么选B,would为什么不能用will,分析每个选项,
答
虚拟语气,要推后一个时态；
也即,现在时变过去式,一般将来变过去将来时
本句是对现在虚拟,一般结构：If +一般过去（be作谓语时变were）,从句用过去将来时或may/might/could+do
A错在问对方看法时,是对方现在（当下）的看法,肯定用一般现在时do you
C虚拟语气未用
D虚拟语气用错,这是 will/may/can +have+done 是对过去虚拟的用法
虚拟语气 在 描述一种本不可能发生的事件的假想情况 时常用到.
又如：If I were you,I would marry him.
如果我是你,我（现在）会嫁给他的.