The Effect of English Proficiency on Korean Undergraduates' Expression of Epistemic Modality in English Argumentative Writing

The present study investigated the effect of English proficiency on the expression of epistemic modality in English argumentative writing produced by Korean undergraduates. It compared three levels of learner corpora with each other and with a corpus of native speaker writing. The findings point to three aspects of L2 writing development with regard to epistemic modality. First, higher level writers utilized a broader range of types of epistemic devices than did the lower level writers. Second, concomitant with higher proficiency was a more even distribution of grammatical classes of epistemic items through greater reliance on modal verbs, nouns and adjectives and less dependence on lexical verbs and adverbs. The higher proficiency writer also exhibited a greater ability to use combinations of epistemic devices from different grammatical classes in diverse syntactic contexts. Third, relatively more skilled writers employed fewer epistemic devices from the semantic category of certainty and more from probability than less skilled ones. From a developmental viewpoint, these concurrent modifications in the use of epistemic devices indicate in the learners' progressive approximation to native-speaker-like expression of epistemic modality.