英文疑難, 請高人指點

The difference is below:
care of (somebody)= 轉交idiomatic use; = in care of (somebody) = abbreviation: c/o; It is used when writing to someone at another person's address = 此信由某人(非真正收信人) 轉交予真正收信者
e.g. To : Ms YYYY
c/o Mr. XXXX
真正收信人為 Ms YYY
此信由 Mr. XXXX轉交予Ms YYY; 信上地址為Mr XXXX的地址。
e.g Write to him care of his lawyer
寫給他的信由他的律師轉交。(地址是律師的地址)

on behalf of (somebody) = as the representative of somebody or instead of them代表或代替某人
e.g On behalf of the department I would like to thank you all.
我謹代表全系,感謝大豕。
e.g Mr. Wong cannot be here, so his wife will accept the prize on his behalf.
王先生不能來,因此由他的夫人代他領獎。

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