摘要
Topic effect on L2 writing has long been an issue of controversy. This study was carried out to investigate the influence of topic type on the quality of topic sentence. The participants, 150 college students at three different proficiency levels, were asked to write both on a private topic and a public topic. The results show that the participants on the whole wrote better on the public topic, and their proficiencies can be differentiated by the quality of their topic sentences. The public topic was conducive to the production of complete English discourse structures, as well as the generation of informative and predictive topic sentences. Moreover, the results also reveal the dynamic nature of contrastive rhetoric
