信息理论是系统功能语法的重要内容。话元是会话结构的最小单位。话元转换指的是发话由一方转移到另一方的过程。话元转换分为打断性转换和非打断性转换,非打断性转换有其内在动力和作用模式。本文运用信息理论,构建了非打断性话元转换的动力模型,并将其运用到篇章研究中。 Information theory is an important part of system functional grammar. A cell is the smallest unit of a conversation’s structure. Phone conversions refer to the process of transferring a speech from one party to another party. There are two types of conversions: interrupted conversions and non-interrupted conversions. Non-interrupted conversions have their inherent motivation and mode of action. In this paper, we use information theory to build a dynamic model of non-interruptive conversions and apply it to the study of the texts.