求问大家推荐信格式

下面这两种格式，大家都用哪种啊？还是有别的更好的
1. Department of XX
XX University School of XX

Dear admission committee,

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Yours sincerely

Prof. XX
2.(这个是51里面看到的)

To whom it may concern,(or Dear sir or madam)

正文

Yours sincerely,

Prof.XX
Department of XX
XX University School of XX