我是大专的学生,期末英语说考商业信函,我想问一下那个怎么写啊,在线...答:写商务信函的原则(Writing Principles)已从原来的3个“C”(Conciseness, Clearness, Courtesy)发展到目前的7个“C”:Completeness(完整), Clearness(清晰), Concreteness(具体), Conciseness(简明), Correctness(正确), Courtesy(礼貌), Consideration(体谅)实例Dear Sirs, With reference to your letter of April 9...