a number of 与several和only a few的区别

a number of 与several和only a few的区别 a number of 、the number of、little 、 few、 several 的相关用法及区别.谢谢 several与a few的区别和用法 a few 和 several 的区别 a few,some,several,a lot of的用法和区别 only few和only a few的区别 a few和several之间的区别是什么? only a few .quiet a few .only a little 和 quiet a little的区别 a few of与a few的区别? few与several的区别 the number of 与 a number of 的区别 the number of与a number of的区别是什么?