| This contrastive study compared Vietnamese students' argumentative ESL essays with model texts composed by native expert writers in Vietnamese and American English. It identified several key differences between English and Vietnamese in terms of rhetorical features, explaining why the ESL writing deviates noticeably from native English texts. These deviations, supported by both quantitative and qualitative evidence, can be attributed to several factors, including ESL writers' over-dependence on textual links and shared schema to maintain coherence, nonlinearity patterns in argument, tendency of making abrupt switches in topical Themes, dependence on personal opinions instead of objective observations, preference for generic examples over concrete details, and use of overtly assertive language. These factors may cause negative reactions from English readers, who may find that ESL argumentative texts are more disconnected, harder to follow, less persuasive, and less well-supported. Vietnamese students may have difficulties in addressing these problems since they often are a combined effect of lack of proficiency, undesirable side-effects of L2 instruction and unconscious negative L1 transfer.;Observed interactions between rhetorical features indicate that differences between L2 and native writings may not be attributed to a single feature, but rather a combined effect of several features of different meaning types. Hence, although this dissertation confirms the key premise of contrastive research (i.e., L1 background is influential in the manner native speakers write in L2), it gives substantive default for such a claim by pointing to a trinocular analysis, which examines data in terms of all three discourse planes as well as possible interactions between the resources used to express these planes.;This study constitutes a step towards the ultimate need of contrastive studies: a coherent and implementable framework that can be shared among different studies. Developed within the SFL framework, I expand a set of relevant analytical tools, providing specific coding guidelines to not only allow for a more all-round and systematic analysis of the text but also facilitate cross-language comparison. The results demonstrate that the SFL framework can serve as the needed unified theoretical foundation that helps contrastive analysis in L2 writing to eventually achieve a full status as a field. |
