Epistemic Modality And Its Realization In Discourse

This thesis carries on the research of epistemic modal meaning(EMM), the meaning of probability, and its realization-epistemic modal expression(EME). It points out that there exists a systemic correspondence between EMM and EME. It also argues the important role played by context in the process of understanding and expressing EMM. According to such a research, this thesis also presents a detailed analysis of the EMM and the EME in the detective novel Death on the Nile. The conclusion of the discourse analysis confirms the research.This thesis falls into four parts.Chapter one is the introduction. It introduces the background of this research and makes clear the contents, purpose, significance, scope and method of this research. It also clarifies the relative definitions in this thesis.Chapter two presents a detailed description of the EMM and EME systems. First, it discusses the previous research by Halliday and Simpson. Second, it explains the characteristics of EMM and the change of orientation and value by which twelve types of EME can be generated. The author argues that the context takes effect in the process of understanding and expressing EMM and depicts how the change of contextual factors causes the change of EMM and EME. Meanwhile, there is also additional explanation about the problems of tense, negation, interrogation, and zero modal element of EME which supplies operational rationale to the following discourse analysis.Chapter three is discourse analysis. The discourses come from the detective novel Death on the Nile. At the outset, this chapter selects several characters' EME and sorts them according to the EME classification. It then explains how the change of contextual factors causes the change of EMM which determines the addresser's selection of EME and how the contextual factors interfere with the addressee'sunderstanding of EMM. The conclusion of the analysis supports this thesis' research.The last part is a conclusion of the whole thesis. While summarizing the contributions of this research, it suggests the pedagogical implications in English teaching as a foreign language. Moreover, it also points out its insufficiencies.