Using a CEFR-Aligned Online System to Enhance Low-Proficiency EFL Learners' Vocabulary Knowledge and Retention

Abstract

Background and Aims: Despite decades of instruction, vocabulary limitations persistently obstruct low-proficiency EFL learners from proficiency and communicative competence. This study aimed to develop and evaluate a CEFR-aligned online vocabulary strengthening system designed to enhance the lexical knowledge of low-proficiency learners at the A1-A2 levels. Methodology: The designed platform integrates 349 words in nine categories with multimodal input, including word forms, pronunciation, illustrations, parts of speech, definitions, usage in context, and self-assessment exercises. A mixed-methods approach employing a one-group pretest-posttest design was implemented. The participants were 32 (N=32) first-year university students with low English placement scores. Data were collected through pre- and post-tests, a retention test, and user feedback forms. Results: The results indicated that the posttest scores were significantly higher than the pretest scores (p < .05) with a large effect size (Cohen’s d = 1.09), indicating a substantial enhancement in vocabulary knowledge. The system also demonstrated high learning efficiency (E = 1.79) and a strong short-term retention rate (92.16%). Qualitatively, user feedback indicated high satisfaction with the platform's ease of use and visual content. However, the small sample size and the lack of a control group may limit the generalizability of the findings. Conclusion: These findings suggest that the CEFR-aligned online system serves as an effective pedagogical tool for bridging the lexical gap for low-proficiency learners in higher education contexts.