I don't know when we shall leave for Moon Bay.(改为简单句)为什么用to?
问题描述：
I don't know when we shall leave for Moon Bay.(改为简单句)为什么用to?
原来的题目是：
I don't know when we shall leave for Moon Bay.（改为简单句）
I don't know when _____ _____for Moon Bay.,空格中填 to leave,为什么用to?
今天就要.
我知道是to leave 那为什么用to
答
to leave
因为I don't know when .
这种表示将来意义的宾语从句,可以用W疑问词+不定式,不定式有将来的意义.