محمدایمان عسکری

Background: While vocabulary acquisition models have been widely studied, the comparative role of Laufer’s frameworks in digital environments—particularly their effects on learner engagement and perception—remains underexplored. This research addresses this gap by examining how these models mediate vocabulary learning outcomes among Iranian EFL learners. Aims: This study aimed to investigate the impact of Laufer’s Three "I" model (Input, Instruction, Involvement) and the extended Five "I" model (adding Interaction and Interpretation) on Iranian EFL learners' deliberate and incidental vocabulary learning engagement in digital contexts. Methods: The study employed a sequential mixed-methods design with 93 intermediate-level male EFL learners (aged 16–20) selected via convenience sampling from private language institutes in Tehran. After homogeneity screening using the Oxford Quick Placement Test (OQPT), 60 participants were randomly assigned to experimental (digital-based instruction) and control (traditional face-to-face) groups. Data were collected through vocabulary tests, engagement surveys, and semi-structured interviews, analyzed using SPSS (v.26) for quantitative data (ANOVA, t-tests) and thematic analysis for qualitative responses. Results: Results indicated that the Five "I" model significantly outperformed the Three "I" model in both deliberate (p< 0.05, d= 0.85) and incidental (p< 0.05, d= 0.72) vocabulary learning. Qualitative data revealed enhanced engagement, reduced anxiety, and improved metacognitive awareness among learners using the progressive model, particularly through its Interaction and Interpretation components. Conclusion: The findings suggest that Laufer’s expanded Five "I" model offers a more effective framework for digital vocabulary instruction by integrating social-interactive and interpretive elements. Educators should prioritize structured yet interactive digital activities to maximize lexical acquisition and learner motivation in EFL contexts.