| Acknowledgement | 第1-5页 |
| Abstract | 第5-8页 |
| 摘要 | 第8-10页 |
| Abbreviations | 第10-11页 |
| List of Figures | 第11-12页 |
| List of Tables | 第12-16页 |
| Table of Contents | 第16-20页 |
| Chapter 1 Introduction | 第20-27页 |
| ·Rationale for the study | 第20-25页 |
| ·Purposes of the study | 第25页 |
| ·Organization of the dissertation | 第25-27页 |
| Chapter 2 Literature review | 第27-78页 |
| ·Pragmatic competence and second/foreign language (L2) learning | 第27-37页 |
| ·Pragmatic competence | 第27-29页 |
| ·Communicative competence | 第27-28页 |
| ·The pragmatic component of communicative competence | 第28-29页 |
| ·Interlanguage pragmatics (ILP) | 第29-31页 |
| ·Theories of development in L2 pragmatic competence | 第31-37页 |
| ·Cognitive processing | 第31-34页 |
| ·Acculturation model | 第34-35页 |
| ·Sociocultural theory | 第35-36页 |
| ·Language socialization | 第36-37页 |
| ·Epistemic modality as an aspect of pragmatic competence | 第37-56页 |
| ·Conceptualization of epistemic modality | 第37-50页 |
| ·Definition and types of modality | 第37-40页 |
| ·Definition of epistemic modality and epistemic devices | 第40-43页 |
| ·Categorizations of epistemic modality | 第43-46页 |
| ·Linguistic realizations of epistemic modality in English | 第46-50页 |
| ·Pragmatic and functional approaches to epistemic modality | 第50-56页 |
| ·The speech-act theoretic approach | 第50-52页 |
| ·The functional approach | 第52-53页 |
| ·The politeness approach | 第53-56页 |
| ·Empirical studies of epistemic modality in ILP | 第56-69页 |
| ·Nonnative speakers use of epistemic devices | 第56-62页 |
| ·Non-corpus-based studies of learner performance | 第57-58页 |
| ·Corpus-based native-nonnative contrastive studies | 第58-62页 |
| ·Nonnative speakers development in the use of epistemic devices | 第62-64页 |
| ·Possible factors influencing learners performance | 第64-68页 |
| ·ILP studies of epistemic modality in mainland China | 第68-69页 |
| ·Comments on the existing studies of epistemic modality in ILP | 第69-78页 |
| ·Theoretical issues | 第70-75页 |
| ·The choice of theoretical construct of L2 pragmatic acquisition | 第70-73页 |
| ·The choice of explanatory frameworks of epistemic-modality use in discourse | 第73-75页 |
| ·Inadequacies of the existing empirical studies | 第75-78页 |
| Chapter 3 Methodology | 第78-96页 |
| ·Research questions | 第78-79页 |
| ·Corpora and instruments | 第79-85页 |
| ·Subjects | 第79-80页 |
| ·Instruments | 第80-81页 |
| ·Data collection and transcription procedures | 第81-82页 |
| ·Native speaker comparison corpus | 第82-83页 |
| ·The comparability of the two corpora | 第83-85页 |
| ·A classification scheme of epistemic devices | 第85-91页 |
| ·Data coding and analysis | 第91-96页 |
| ·Source of the list of epistemic devices under investigation | 第91-92页 |
| ·The tagging format | 第92-93页 |
| ·Analytical tools | 第93-94页 |
| ·Procedures of data coding and analysis | 第94-96页 |
| Chapter 4 Results and discussion: Use of epistemic devices in comparison | 第96-135页 |
| ·Overall distribution | 第96-101页 |
| ·Overall frequency and variety of devices | 第96-98页 |
| ·Grammatical distributions | 第98-99页 |
| ·Categories of epistemic devices | 第99-101页 |
| ·Distribution of boosting epistemic devices | 第101-109页 |
| ·Overall patterns | 第101-102页 |
| ·Distribution across boosting subcategories | 第102-109页 |
| ·Modal verbs | 第102-103页 |
| ·Adverbs | 第103-104页 |
| ·Lexical verbs | 第104-106页 |
| ·Adjectives | 第106-107页 |
| ·Nouns | 第107-108页 |
| ·Multiword expressions | 第108-109页 |
| ·distribution of hedging epistemic devices | 第109-128页 |
| ·Overall patterns | 第109-110页 |
| ·Distribution across hedging subcategories | 第110-128页 |
| ·Modal verbs | 第111-112页 |
| ·Adverbs | 第112-117页 |
| ·Lexical verbs | 第117-120页 |
| ·Adjectives | 第120-123页 |
| ·Nouns | 第123-127页 |
| ·Multiword expressions | 第127-128页 |
| ·Discussion | 第128-135页 |
| ·Learners pragmatic competence in the use of epistemic devices | 第128-130页 |
| ·Possible contributing factors to the non-native performance | 第130-135页 |
| Chapter 5 Results and discussion: Development in the use of epistemic devices | 第135-175页 |
| ·Variations in the use of epistemic devices across academic years | 第135-155页 |
| ·Overall patterns | 第135-138页 |
| ·Variations in the use of boosters over time | 第138-144页 |
| ·Modal verbs | 第139-140页 |
| ·Adverbs | 第140页 |
| ·Lexical verbs | 第140-141页 |
| ·Adjectives | 第141-142页 |
| ·Nouns | 第142-143页 |
| ·Multiword expressions | 第143-144页 |
| ·Variations in the use of hedges over time | 第144-155页 |
| ·Modal verbs | 第145-146页 |
| ·Adverbs | 第146-149页 |
| ·Lexical verbs | 第149-151页 |
| ·Adjectives | 第151-152页 |
| ·Nouns | 第152-154页 |
| ·Multiword expressions | 第154-155页 |
| ·Variations of performance between high and low proficiency learners | 第155-168页 |
| ·Variation in the use of epistemic devices | 第156-161页 |
| ·Overall features | 第156-157页 |
| ·Differences in the use of boosters | 第157-159页 |
| ·Differences in the use of hedges | 第159-161页 |
| ·Variations of development in the use of epistemic devices | 第161-168页 |
| ·Overall features | 第162-163页 |
| ·Differences in the changes of boosters | 第163-166页 |
| ·Differences in the changes of hedges | 第166-168页 |
| ·Discussion | 第168-175页 |
| ·Developmental features in learners use of epistemic devices | 第168-172页 |
| ·Possible factors influencing learners pragmatic development | 第172-175页 |
| Chapter 6 Conclusion | 第175-184页 |
| ·Recapitulating the major findings | 第175-178页 |
| ·Implications of the study | 第178-182页 |
| ·Theoretical implications | 第178-179页 |
| ·Methodological implications | 第179-180页 |
| ·Pedagogical implications | 第180-182页 |
| ·Limitations of the study | 第182页 |
| ·Directions for future research | 第182-184页 |
| References | 第184-202页 |
| Appendix 1: The writing tasks in the examination scripts | 第202-204页 |
| Appendix 2: List of lexical epistemic devices investigated | 第204-210页 |
| Appendix 3: Coded features from the non-native and native speaker corpora | 第210-218页 |
| 在学期间公开发表论文及著作情况 | 第218页 |
