文档介绍：This paper focuses on parative analysis of Obama ’s inaugural address and mencement speech at Barnard College from the perspective of three metafunctions in Systemic-Functional Grammar to explore how Obama adjusts his language to meet the theme of these two speeches and his different intentions in these two speeches. The addresser of these two speeches in the same: President Barack Obama. The background, the audience, the aims of the speaker and the relationship of the speaker with the audience differ in these two speeches. The audience in the inaugural address is the American people or people all over the world who watch his address through TV or radio . In this inaugural address, Obama aims to get trust and support of American people and convince them that his government can lead them out of the economic crisis. The audience in mencement speech at Barnard College is the graduating students. In this speech, Obama aims to encourage them to bravely face the future and shoulder their responsibilities. As the themes of these two speeches differ, Obama adopts language features to meet his according aims in these two speeches, which can be revealed in the three matafunctions of these two speeches. The following isa summary of the analysis of these two speeches. Ideational function is mainly realized by transitivity system and voice system. Transitivity system is made up of six proce