This study investigated how ChatGPT can enhance L2 email writing, specifically focusing on politeness. Twenty-nine Korean university students were asked to draft an email in class requesting a recommendation letter from an English-speaking professor.
For the assignment, they submitted their initial drafts to ChatGPT to receive guided feedback. Subsequently, they revised their drafts based on the politeness features observed in the ChatGPT-generated model email. Four days later, the participants wrote the same email again in class without ChatGPT’s assistance. The three versions of the emails were analyzed for address forms, levels of directness in the requests, and external modifications. The results indicated that ChatGPT had a significant immediate impact on the use of politeness features in the emails; however, many of these improvements diminished in the delayed post-task, except for sustained gains in email closings. These findings suggest that while ChatGPT can lead to immediate enhancements in L2 email politeness, explicit instruction may be necessary for ensuring long-term retention of these features.