A Study On American Public Service Advertising Based On Multimodal Discourse Analysis

With the advent of the information age and the development of multimedia technology,advertising has become an indispensable part of people's life.As a special kind of advertisements,PSA(public service advertising)shoulders the mission of promoting the development of human society,while the United States is the cradle of the birth of PSA,which promotes the development of global public service advertising.Therefore,American PSAs have great research significance.The multimodal theory has been paid attention in various fields at the beginning and provided a new perspective for discourse analysis.PSA as a multimodal discourse,including languages,images,colors,sounds,etc,is an ideal research object.This paper based on Systemic Functional Grammar and Visual Grammar,to make a comprehensive multimodal discourse analysis about American PSAs.The multimodal discourse analysis in the paper is divided into two parts: the first is about the print PSAs,the second is about video PSAs.The main research findings are as follows: first,American public service advertising is mainly composed of the visual modality,the auditory modality and the verbal modality.In verbal modality,the first and second personal pronouns and their possessive forms are used to shorten the psychological distance between the image and the viewer,thus reflecting the persuasion and persuasion effect of PSAs.Second,through the analysis of the representational meaning of advertisements,this paper found that most video PSAs account for narrative processes,while most print PSAs are conceptual processes.Thirdly,the modes relations in American PSAs are mostly complementary.