韩礼德将语言的基本功能归纳为三大元功能：概念功能、人际功能和语篇功能。所谓人际功能，就是指讲话者运用语言与别人交往，用语言来建立和保持人际关系的功能。语言除了传递信息的作用之外还有具有表达讲话者身份、地位、态度、动机，同时影响和改变别人的态度、观点与行为等互动作用。人们在交流过程中为了表达一定的意义，就要在语言系统中进行有目的的选择。过去的在人际意义方面的研究很大一部分集中在书面和口头两种传统的交流方式上。随着因特网的出现，以计算机为媒介的交流（CMC）扩展了体现人际意义的语言载体。互联网文化引发了计算机技术、社会学、心理学、哲学等各个领域对其的研究，也为语言学的研究增添了新内容。有些学者认为，CMC的交流途径只限于文字符号而缺乏个人情感因素，不利于友好人际关系的形成。也有学者从社交信息加工角度分析，认为可以通过CMC建立人际关系。迄今为止，对CMC的研究主要集中在从社会学、社会心理学和社会行为学等角度出发研究网络虚拟社区的行为，或是从语言学角度研究网络语言兼具书面口语特征的二象性及网络对语言形式的影响。本文以系统功能语言学及语用学中礼貌原则为主要理论框架，对CMC的一种特殊表现方式—清华大学网络学堂的课程讨论语言进行研究，探讨CMC参与者是如何采用不同的语言学手段实现语言的人际功能，体现人际意义的。研究发现，参与网络学堂讨论的学生在网络环境中选择了多种语言学手段来实现语言的人际功能，维持人际关系。本文详细研究探讨了网络课堂上学生如何通过情态、人称系统和礼貌原则等手段来实现语言的人际功能。本研究从一个特殊的角度出发探讨语言的人际功能，在一定意义上在某些方面丰富了韩礼德的语言人际功能理论，也将人际意义的研究对象扩展到一个新的领域。同时，本研究也帮助英语学习者进一步认识语言功能与语言形式之间的关系，从而更深刻地理解英语语言，学好用好英语。
Many linguists previously have studied the interpersonal meaning of language. According to M.A.K Halliday, the interpersonal metafunction enacts social relationships. Interpersonal meaning is described as “meaning as a form of action: the speaker or writer doing something to the listener or reader by means of language.” In order to express a certain meaning, people tend to choose among different expressions during the process of communication. Communication includes both spoken language and written language. As a result of the Internet’s development, however, computer-mediated communication (CMC) has extended its reach as a carrier of interpersonal meaning. CMC shares many of the characteristics of spoken and written language. This study will show how there are various strategies which can be employed to project interpersonal meaning via the Internet. The previous research on interpersonal relationships in CMC has focused on media studies, social psychology and social ethology, but there has been little research which analyzes interpersonal relationships from a strictly linguistic point of view. Some linguists focus on the CMC spoken-written duality, not the interpersonal relationship.This research is carried out within the theoretical framework of systemic-functional grammar and politeness theory. It is based on the data provided by the discussions on the Tsinghua University ClassNet. This thesis will show how interpersonal meaning is realized using linguistic devices. The results show that the participants in these Internet discussions DO adopt linguistic devices and strategies such as modality, person system, politeness strategies, etc. to maintain interpersonal relationship. Then I study how the students realize the interpersonal metafunction of language namely in modality, person and politeness strategies etc. This study seeks to broaden and to enrich Halliday’s interpersonal metafunction to some degree and provide a new framework for CMC study. Besides, the study shows EFL learners the relationship between form and meaning in English to help them learn English better.
