Listening Fades Faster Than Words: Learner-Log Evidence for Planning Review in Technology-Supported EFL Practice

Introduction: English language teachers and learning apps recycle vocabulary routinely, but listening practice is rarely scheduled for review, and it is not known how quickly the benefit of L2 listening practice fades.Purpose: The study examined whether L2 listening knowledge fades faster than word knowledge between practice opportunities, and how much planned review can offset that loss under realistic learner dropout.Method: Three public learner-log datasets were analysed: 4.7 million TOEIC listening responses from 16,682 EdNet learners, and word-level practice records from two Duolingo datasets. Logistic regression models estimated forgetting slopes, controlling for proficiency and practice history; predictions were evaluated on held-out learners; and 12-week course scenarios calibrated on the estimates compared five review plans.Results: For items a learner had answered correctly before, the odds of answering correctly again declined about seven times more steeply with time for listening items than for vocabulary items (slope −0.355 vs −0.048; difference 0.306, 95% CI [0.270, 0.343]). Adding time since practice improved predictions of listening re-attempts (1.13% lower log-loss) but not of vocabulary. Only 21.7% of learners practised beyond their first week. In the scenarios, timed review raised end-of-course listening recall by 1.1 percentage points over new-material-only practice and by 0.9 points over a fixed Leitner schedule, while knowing each learner's true memory added only 0.2 points more.Conclusions: Listening material should be recycled deliberately within days of successful practice; simple expanding schedules capture most of the benefit of review; and keeping learners practising matters more than fine-tuning review timing. Preprint. Not yet peer reviewed.