Automated Written Corrective Feedback 4-6

Background: Second language (L2) writing development is influenced by the interaction of grammatical control, revision processes, and instructional focus. The Holistic Error and Instructional Mapping (HEIM) framework provides a data-driven approach for identifying key grammatical subsystems that influence writing performance and for establishing instructional priorities.Purpose: This study investigated writing development and instructional priorities in a university English as a foreign language (EFL) course using the HEIM framework. It examined whether writing scores improved across drafts, which grammar components predicted final writing quality, whether learners formed distinct developmental profiles, and which areas should be prioritized instructionally. Methods: The dataset included pretest and posttest writing scores and four grammar quiz components-sentence patterns, main verb, agreement, and mechanics-from 27 undergraduate EFL learners. A paired-samples t-test was conducted to assess changes in writing scores across drafts.