Take care of the pence, and the pounds will take care of themselves.
积少自然成多。
speak for itself/themselves
不言而喻；有目共睹
the facts speak for themselves
事实足以说明一切
柯林斯高阶英汉双解学习词典释义
PRON-REFL
他们自己;她们自己;它们自己
You use themselves to refer to people, animals, or things when the object of a verb or preposition refers to the same people or things as the subject of the verb.
You use themselves to emphasize the people or things that you are referring to. Themselves is also sometimes used instead of 'them' as the object of a verb or preposition.
(用以代替himself or herself，指代句子的主语，而不指明是男是女;有人认为这种用法不对)
You use themselves instead of 'himself or herself' to refer back to the person who is the subject of sentence without saying whether it is a man or a woman. Some people think this use is incorrect.
(用以代替 himself or herself，强调所指代的人，但是不指明是男是女; themselves 有时也用作动词或介词的宾语;有人认为这种用法不对)
You use themselves instead of 'himself or herself' to emphasize the person you are referring to without saying whether it is a man or a woman. Themselves is also sometimes used as the object of a verb or preposition. Some people think this use is incorrect.