| Acknowledgements | 第1-7页 |
| Abstract （English） | 第7-9页 |
| Abstract （Chinese） | 第9-11页 |
| CHAPTER ONE INTRODUCTION | 第11-24页 |
| 1．1 The definition of instructions in this research | 第11-14页 |
| 1．2 Two basic functions of instructions in the EFL classrooms | 第14-17页 |
| 1．3 The significance of teacher's instructions in language teaching and SLA | 第17-20页 |
| 1．4 Purpose of the present study | 第20-22页 |
| 1．5 Overview of the paper | 第22-24页 |
| CHAPTER TWO LITERATURE REVIEW | 第24-48页 |
| 2．1 Previous studies of instructions | 第24-28页 |
| 2．1．1 General guidelines of giving instructions | 第24-27页 |
| 2．1．2 Studies on language functions of instructions | 第27-28页 |
| 2．2 Related theoretical perspectives on instructions | 第28-35页 |
| 2．2．1 Instructions as the procedural language | 第28-30页 |
| 2．2．2 Feuerstein's theory of meditation on instructions | 第30-33页 |
| 2．2．3 Simplified input on instructions | 第33-35页 |
| 2．3 Input modification of teacher talk | 第35-42页 |
| 2．3．1 The effect of temporal variables on listening comprehension | 第37-38页 |
| 2．3．2 The effect of lexis on listening comprehension | 第38-39页 |
| 2．3．3 The effect of syntax on listening comprehension | 第39-40页 |
| 2．3．4 The effect of discourse on listening comprehension | 第40-42页 |
| 2．4 The relationship between instructions and SLA | 第42-44页 |
| 2．5 The relationship between instructions and communicative language teaching | 第44-47页 |
| 2．6 Summary | 第47-48页 |
| CHAPTER THREE METHODS AND PROCEDURES | 第48-59页 |
| 3．1 An introduction of the corpus and the analytical Tool （MCO） in this research | 第48-51页 |
| 3．2 Procedures | 第51-59页 |
| CHAPTER FOUR RESULTS AND DISCUSSION | 第59-95页 |
| 4．1 The general descriptions on Chinese Junior Middle School teachers' instructions in the research data | 第59-77页 |
| 4．1．1 Realization of simplifying instructions by pauses on temporal variables in EITC | 第60-62页 |
| 4．1．2 High frequency language expressions to direct the students' actions on lexis in EITC | 第62-63页 |
| 4．1．3 Realization of simplifying instructions by sentence types on syntax in EITC | 第63-65页 |
| 4．1．4 Realization of simplifying instructions by comprehension checks on discourse in EITC | 第65-66页 |
| 4．1．5 Realization of simplifying instructions by self-repetitions on discourse in EITC | 第66-74页 |
| 4．1．6 Expressions of initiating instructions on discourse in EITC | 第74-76页 |
| 4．1．7 Realization of simplifying instructions by discourse markers in EITC | 第76-77页 |
| 4．2 Factors that are conducive to ineffective instructions in the EFL classrooms of Chinese junior middle schools | 第77-82页 |
| 4．2．1 No appropriate substitution | 第78-79页 |
| 4．2．2 Fuzziness of referent | 第79-80页 |
| 4．2．3 Redundant speech | 第80-82页 |
| 4．3 Comparative studies on three language functions of Chinese Junior Middle School teachers' instructions in the research data | 第82-91页 |
| 4．3．1 Commands as expressions to give instructions in CJMS | 第83-85页 |
| 4．3．2 Requests as expressions to give instructions in CJMS | 第85-86页 |
| 4．3．3 Suggestions as expressions to give instructions in CJMS | 第86-88页 |
| 4．3．4 Total distributions of commands, requests and suggestions in CJMS | 第88-90页 |
| 4．3．5 High frequency expressions to give instructions in CJMS | 第90-91页 |
| 4．4 Concluding comments | 第91-95页 |
| CHAPTER FIVE CONCLUSIONS | 第95-102页 |
| 5．1 Conclusions of major findings | 第95-99页 |
| 5．2 Implications | 第99-100页 |
| 5．3 Limitations of this research | 第100-102页 |
| Bibliography | 第102-108页 |
| Appendix 1 | 第108-109页 |
| Appendix 2 | 第109-110页 |
