| Abstract | 第1-7页 |
| 摘要 | 第7-11页 |
| Introduction | 第11-15页 |
| Introduction to the research | 第11-12页 |
| Motives for the research | 第12-13页 |
| The significance of the research | 第13页 |
| Outline of the research | 第13-15页 |
| 1 Literature Review | 第15-44页 |
| ·Overview of politeness theories | 第15-39页 |
| ·Studies on politeness strategies in business settings | 第39-42页 |
| ·The definition and classifications of business letters | 第42-44页 |
| 2 Methodology | 第44-46页 |
| ·Subjects | 第44页 |
| ·Research questions | 第44-45页 |
| ·Research procedures | 第45-46页 |
| 3 Data analysis and results | 第46-78页 |
| ·Contrastive analysis of positive and negative politeness strategies at three stages | 第46-47页 |
| ·Contrastive analysis of positive and negative politeness strategies in six types of letters | 第47-48页 |
| ·Contrastive analysis of text-position of positive and negative politene | 第48-51页 |
| ·Contrastive analysis of letter-specific text-distribution of politeness categories | 第51-55页 |
| ·Analysis of characteristics and problems in linguistic productions of politeness strategies used by CELs | 第55-76页 |
| ·Possible causes | 第76-78页 |
| Conclusion | 第78-82页 |
| Summary of Main Findings | 第78-80页 |
| Pedagogical Implications | 第80页 |
| Limitations and Suggestions for Further Study | 第80-82页 |
| Acknowledgements | 第82-83页 |
| References | 第83-88页 |
| Appendix I Writing Experiment | 第88-90页 |
| Appendix II Raw Data | 第90-95页 |
