Abstract

This study examined the impact of two types of L1-mediated written corrective feedback—direct and indirect hybrid (indirect plus metalinguistic)—on L2 writing. Twenty-six Korean university students, at beginner to intermediate proficiency levels, completed a three-stage revision task: an initial draft, a first revision after receiving feedback, and a second revision without further assistance. Participants were divided into two groups, each receiving L1 feedback via ChatGPT: one group received direct feedback, and the other received indirect hybrid feedback. Uptake was analyzed across five writing components: content, organization, grammar, vocabulary, and mechanics. Both feedback types significantly improved writing after the first revision, with the most substantial uptake observed in mechanics and grammar. However, uptake decreased in the second revision, particularly in content and organization, and new or reintroduced errors were common. Notably, direct feedback proved more effective for beginner-level learners in later revisions, specifically for structural improvements and overall uptake. Conversely, intermediate learners benefited more from indirect hybrid feedback, especially in content development. These findings suggest that feedback effectiveness may vary with learner proficiency, offering pedagogical implications for customizing AI-mediated feedback in L2 writing instruction.