by oneself与for oneself 有什么区别?

by oneself与for oneself 有什么区别? by oneself ,of oneself,for oneself有什么区别 by oneself与for oneself的区别 oneself与by oneself有什么不同 by oneself 和 for oneself 的区别 by oneself/for oneself by oneself和on oneself有什么区别？ for oneself ,by oneself ,of oneself的区别 oneself与by oneself的区别 for oneself 和 of oneself 有什么区别 by oneself 与on one's own 有什么区别? to oneself,by oneself,for oneself用法