few ,a few,little,a little有什么区别?哪些修饰可数名词?哪些是比较级前面可以加的?

a few,few 后面一般跟可数名词
前者肯定(有几个),后者否定(没几个)
there are a few students in the class 教室里有几个学生
there are few students in the class 教室里没几个学生(表否定)
a little,little 后面一般跟不可数名词
前者肯定(有几个),后者否定(没几个)
a little snow in the yard 院子里有点雪
little snow in the yard 院子里没多少雪