A Corpus-based Study Of Causal Links In College English Textbooks

Nowadays,the focus of linguistic study has been shifted from the level of sentence to discourse. According to Halliday's cohesion theory, the discourse links signal the logic relationships between the propositions in lines and thus enable the reader to effectively figure out the complex logic relations in discourse as well as to predict the text structure or to presume the writers'attitude. So the discourse links are important in English learning.As the formal channel of knowledge acquisition, textbook, of course, should not neglect this important discourse links and the corresponding training as well. Therefore, this thesis focuses on exploring how well the present College English textbooks do on this aspect. For lack of time and space, an investigation is only conducted on the use of causal links in the texts of two popular College English textbooks—College English and 21st Century College English.The present thesis conducts a comparative study on the causal links in the two commonly-used College English textbooks. It adopts the qualitative and quantitative methodology to analyze the differences of use of causal links between the two sets of textbooks and between the textbooks and corpora. This study mainly concentrates on the following three questions: How well the present College English textbooks do from the aspect of the discourse links? Do the two sets of textbooks use the causal links to the same extent as the natives? What are the features in the use of causal links in the textbooks respectively comparing with the native and learner corpus? This study attempts to analyze the use of causal links in College English textbooks and propose some suggestions regarding teaching and learning so as to raise teachers'and learners'understanding of causal links.The thesis consists of four chapters. Chapter one serves as an introduction,which introduces the research background, purpose and significance of the study, and research design briefly. Chapter two presents general reviews of the researches of different linguists and scholars relevant to the current study and relevant concepts used in this study. Chapter three is the quantitative and qualitative study of the features of causal links in two sets of textbooks, reporting the statistical results and major findings obtained by comparison with the corpora. Finally,the conclusion is drawn in Chapter Four.