Investigating the Effects of L1 and L2 Paper-based Glosses and Their Presentation Formats on EFL Learners' Incidental Vocabulary Acquisition

While there is a substantial body of research on the role of glosses in fostering reading comprehension and vocabulary acquisition, the findings on relative efficacy of first language (L1) and second language (L2) glosses are conflicting. This study investigates the impact of Farsi (L1) and English (L2) paper-based glosses with different presentation formats (in the margin and at the bottom of page) on intermediate-level English as a foreign language (EFL) learnerschr('39') vocabulary retention and recall. During a two-month treatment, the participants read the passages under one of the four conditions: L1 gloss in the margin (L1-margin), L1 gloss at the bottom of the page (L1-bottom), L2 gloss in the margin (L2-margin), and L2 gloss at the bottom of the page (L2-bottom). Following the treatment, a vocabulary post-test and a month later, a delayed post-test were administered to gauge any vocabulary gains. Results of repeated measures ANOVAs showed the superiority of L1 over L2 glosses (L1-margin> L1-bottom>L2-margin>L2-bottom) in the post-test. The delayed post-test scores revealed the better performance for marginal glosses, regardless of the language of the gloss (L1-margin = L2-margin > L1-bottom > L2-bottom), suggesting that how learners process and retrieve lexical items may vary depending on both language and location of the gloss.