求翻译：商务英语信函是各国贸易交往最常用的一种书面传递工具，也是一门专业性很强的应用文体。本文从得体准则、一致准则、慷慨准则、赞誉准则、谦虚准则、同情准则方面来分析了礼貌原则在商务英语信函中的应用，并且结合了大量的实例来证明。我们在今后的外贸函电写作中应更加注意礼貌原则的应用，并掌握在商务这一语境中正确运用信函往来来达成交易的方法，从而更好地完成业务交流和促进友谊。是什么意思？

Business English letter a written transfer is the national trade association of the most commonly used tools, is also a strong professional style of application. This article from the appropriate guidelines, consistent guidelines, generous criteria guidelines, codes of praise, humility, compassion criteria to analyze the application of the principle of politeness in business letters, and combined with a lot of examples to prove that. In future correspondence, we should pay more attention to the application of politeness principle in writing and the correct application in the business in the context of this method of correspondence to deal, so as to better meet business exchange and friendship.