Usage-based approaches to assessing syntactic sophistication in second language writing: Interaction of genre and proficiency

Based on usage-based approaches to language learning, this study investigated how second language (L2) writers use verbs and argument structure constructions across different genres, while also exploring how this genre effect interacts with L2 writing proficiency. We analyzed five previously established usage-based indices using a learner corpus comprising argumentative and narrative essays elicited from 3196 college-level learners. Through a series of mixed-effects regression analyses, we identified a consistent genre effect, with argumentative essays featuring a more sophisticated use of verbs and constructions alongside a greater diversity in construction types. Additionally, a significant interaction emerged between genre and proficiency regarding construction frequency and the frequency of verb–construction combinations. These results indicate that while the previously observed genre effect extends to the L2 use of verbs and constructions, its manifestation varies depending on L2 proficiency. Overall, our study supports the usage-based learning of verbs and constructions in the context of L2 writing.