声明
Acknowledgements
摘要
Abstract
Contents
List of Tables
List of Figures
Chapter Ⅰ INTRODUCTION
1.1 Research backgroud
1.2 Research questions
1.3 Significance of the study
1.4 Structure of the Study
Chapter Ⅱ LITERATURE REVIEW
2.1.1 The modality study in semantics
2.1.2 The study of modality in typology
2.2 The study of the meaning of modal verbs
2.2.1 The mono-semantic of modal verbs
2.2.2 Poly-semantic of modal verbs
2.2.3 The fuzzy set modal
2.2.4 Cognitive method of modal verbs
2.3 Previous studies on modal verbs
2.3.2 Modality research at home
2.3.3 Summary
Chapter Ⅲ TH EORETICAL BASIS
3.1 Prototype category theory
3.1.1 The definition and background
3.2 Three kinds of semantic uncertainty
3.2.1 Gradience
3.2.2 Ambiguity
3.2.3 Merger
3.3.2 Three types of models
3.4.1 The prototype theory mapping in may
3.4.2 The prototype theory mapping in must
3.5 Summary
Chapter Ⅳ RESEARCH DESIGN
4.1.4 Error analysis
4.2 Object of study
4.2.2 Modal sequence and modality
4.4 TooIs of study
4.4.1 AntConc3.2.0
4.5 Procedure of research
Chapter Ⅴ RESULTS AND DISCUSSION
5.2 The semantic study of modal verbs
5.2.1 Necessity and obligation
5.2.2 Possibility,permission and ability
5.2.3 Vblition and prediction
5.3 The analysis of the result
Chapter Ⅵ CONCLUSION
6.1 Major findings
6.2 Tentative reasons
6.2.2 InfIuenced by the acquisition time
6.2.3 Influenced by the teaching method
6.2.5 Influenced by the transfer of writing pattern
6.4 Limitations
Refbrences