it isn't rain 与 it doesn' t rain 到底有什么区别,分别在什么情况下使用?
问题描述：
it isn't rain 与 it doesn' t rain 到底有什么区别,分别在什么情况下使用?
I'll go to school if it________rain?
答
doesn't rain ( rain 是动词‘下雨’,it isn't rain这种用法是错的）