美国总统每年发表的国情咨文是典型的政治演讲,具有丰富的人际功能。本文运用系统功能语言学框架下的人际功能模式,从人际功能的两个层面——语气和情态,采取定量和定性相结合的方法,分析备受关注的2011年美国国情咨文,探讨演讲者如何通过人际功能达到演讲的目的。 The State of the Union address issued annually by the U.S. president is a typical political speech with rich interpersonal functions. Based on the interpersonal function model under the framework of system functional linguistics, this dissertation analyzes quantitatively and qualitatively the United States State of the Union Address 2011 from two aspects of interpersonal function - tone and modality, and discusses how the speaker is concerned Through interpersonal function to achieve the purpose of speech.