商务英语写作中，正确地使用语法、拼写和标点符号是非常重要的。但是除了遣词造句外，更重要的是根据接受信息的对象来选择恰当的文字表达方式和语气，要从收件人的角度设想他们将会接受什么样的行文语气，更要考虑到收件人的需要、愿望、兴趣和问题等，这样才能确定的应对方法或方式，达到交流的目的。
　　所以，要想确保沟通的顺畅、达到交流的目的，必须使用恰当的语气。文书中的语气反映着对整个商务事件的关注程度、对于开展合作的诚意及对工作认真负责的态度。无论是开展业务、投标项目，还是在催要欠款、投诉的文书写作中，都要本着解决问题的原则，有力有礼有节地采用合适的语气，既不能盛气凌人、缺乏灵活，也不能恶语相伤、刻薄无理。
　　不同的语气表达出不同的信息，既可以是咄咄逼人，也可以是彬彬有礼。不恰当的语气会导致交流的不快和失败，甚至是事与愿违。所以，根据实际交流的需要来选择和把握好语气的使用至关重要。
　　好消息或正面消息可直截了当地点明主题，但传递坏消息或负面消息时，则一定要语气委婉，尽量避免开门见山直接表明。试比较以下两个例子。
Dear 　　We are shipping today the 10 bolts of CA-65 watered-silk that you ordered last month and they are expected to reach you no later than 15 September. 　　We feel confident that you will be pleased with the material because our newly-set process makes it definitely unshrinkable. 　　Enclosed please find several swathes of the same material in other colors which show you the broad variety that we have available. In the meantime, if you have any special needs, please let me know, and I will give your inquiry my personal attention. 　　Sincerely yours 　　(Signature) 　　William White 　　Sales Manager
Dear Mr. Zhang 　　Thank you for sending us your reservation request. We appreciate your interest in our qualityhotel accommodation. 　　Early reservations for two large convention groups have left us with no free rooms for the weekof March 15. However, we will be happy to arrange an accommodation for you at the GoldenDragon Hotel, a fine hotel, which is directly across the street from us. May we reserve twosingle rooms for you at that hotel? For fast service, please use our Fax number: 86-11-.Our machine will take your message at 24-hour service. 　　Enclosed is a copy of our newest brochure showingsure that it would help you make your best choicesome modified rules in reservation. We arein future. By staying at our hotel you willcontinue to obtain top quality accommodation and the most convenient commercial service. 　　We are looking forward to your visit to Beijing. 　　Sincerely yours 　　(Signature) 　　Li Ping
　　所以，即使是在传递一个负面的信息，也要避免使用消极词语，诸如“We don't”, " Irefuse".“You cannot”, "Your loss is”,“It is impossible that…”、“I am not prepared to”这样的词语。应尽量站在正面的立场上并以积极的、委婉的、乐观的、更具建设性的方式来传递信息，即比较好用委婉(Indirect Order)的语气来表达，也可以通过表示愿意提供帮助来弱化坏消息带来的消极影响。例如，可以这样来表达: 　　If you need any further information, please do not hesitate to contact me. 　　If there is anything I can do for you, please do not hesitate to let me know. 　　为了交流合作的顺利进行，即使责任不在本人，也切忌指责对方。因此，以下表达法在商务写作中要尽量避免使用: 　　You failed to…
We must insist…