Existential Constructions and Syntactic Complexity in Chinese EFL Writing: A Corpus‐Based Comparative Study With ChatGPT ‐Enhanced Analysis

Existential constructions (ECs) play an important role in academic writing by introducing new information, expressing epistemic stance and facilitating information flow. Examining how EFL learners use different EC types can offer valuable insights into their syntactic development and writing proficiency. Previous research, however, has focused mainly on EC acquisition independently, with limited attention to the relationship between constructional usage and sentence‐level syntactic complexity. The present study investigates Chinese EFL learners' use of ECs across three categories: presentational, epistemic/evidential and interrogative forms. A corpus‐based comparative analysis was conducted using four corpora, with ECs extracted via ChatGPT‐assisted annotation and subsequent manual classification. The results show that learners exhibit a restricted EC repertoire. Presentational ECs were significantly overused, whereas contracted forms were categorically absent. Within the epistemic/evidential category, all evidential ECs were completely unattested and most epistemic ECs were significantly underused. Interrogative ECs were pervasively underused, with six forms categorically absent from learner corpora. Regression analysis further indicated that presentational and interrogative EC frequencies are negatively associated with Mean Dependency Distance (MDD), whereas epistemic/evidential EC frequency is positively associated with MDD. These findings underscore the pedagogical implications of promoting constructional diversity, particularly epistemic and evidential forms that are essential to academic discourse.