Cohesive Devices In Engineering Dissertation Abstracts Written By American And Chinese PhD Students

A well-constructed and informative abstract is essential for scholars to conduct academic communication in the world arena, for many search engines for academic purposes only show the abstract. A sound abstract should be coherent syntactically and semantically. Since the publication of Cohesion in English collaborated by Halliday and Hasan in 1976, numerous studies have been performed to investigate the effects cohesion theory exerts on English writing from various respects, but little research has focused on doctoral dissertation abstracts, let alone the consideration of the native language of EFL learners. Thus, this study investigates the use of cohesive devices in engineering dissertation abstracts composed by American and Chinese Ph D students under the framework of Halliday and Hasan’s cohesion theory.To ensure the validity and reliability of the research, we establish three corpora for comparison, 360 doctoral dissertations from Pro Quest and BIT are collected. Grammatical devices are identified with the aid of Ant Conc and Pat Count and lexical devices are identified manually. Differences in cohesive devices between two corpora are tested by log-likelihood calculator.Research results indicate lexical devices are the most frequently used, followed by reference and conjunction devices. Both groups share a similar set of cohesive items. Specifically, they rely strongly on the, this and these, we, it and they for reference and and, but, however, first, finally and thus for conjunction. Repetition is a remarkable characteristic of lexical cohesion in both groups. Significant differences exist in the overall use of cohesive devices as well as in each category between the two groups. Specifically, Chinese Ph D students overuse definite article the, underuse personal and comparative reference, rely heavily on additive, causal and temporal conjunctions but underuse adversative conjunctions, use more repetition and less synonyms. Besides, phenomena of overuse and underuse of certain cohesive items in Chinese Ph D students’ abstracts exist. When cohesive features in Chinese abstracts are identified, we find first language transfer can account for some cohesive features in Chinese students’ English abstracts but it is weakened to some extent due to the high English proficiency of Chinese Ph D students.Finally, probable explanations for the above differences are provided according to first language transfer and cross-cultural divergence to present implications for academic English writing.