By oneself的意思是"单独地"、"靠自己地"( alone or independently)。例：
His father lives by himself in the village.
All his friends have deserted him and he is all by himself now.
For oneself的意义为"为自己"(for himself or for herself)。例：
One should not live only for oneself.
In oneself的意思是"就其本身或本性而言"。例：
This wood is hard in itself.
Of oneself的意思是"自然地"、"自发地"、"自动地"(of one's own accord)。例：
Every day I awake of myself at half past five.
The door opened of itself.
The fire went out of itself.
与上列四个短语相类似的还有两个词组，即beside oneself和 to oneself，前者义："失常"、"发狂";后者是"独自占有或享用"。例：
He was beside himself with joy.
When one dines in a restaurant，one likes a table to oneself.
Oneself和 one's self的区别也是值得我们注意的。Oneself是反身强调代词，意指自己;one's self则是代词加名词，意指个人的本性。它们的区别如同myself和my self;yourself和your self ;himself和his self;ourselves 和our selves ;themselves和their selves一样。例：
She made a cup of tea for herself.
She looked just like her old self.
请注意，myself可以在句中表示me的涵义，这是其他反身代词所没有的特性。例：
They invited my father and myself(=me)to their party.
He saw neither myself nor Mary in the street.
