WHAT WORKS (AND WHAT DOES NOT) IN EFL VOCABULARY INSTRUCTION: A SYSTEMATIC REVIEW WITH IMPLICATIONS FOR TERTIARY-LEVEL TEACHING

Vocabulary knowledge is a core component of second language proficiency and a strong predictor of academic success in English as a Foreign Language (EFL) contexts. Despite extensive research, uncertainty persists regarding which instructional approaches most effectively support sustainable vocabulary development at the university level. This systematic review synthesizes empirical research on EFL vocabulary instruction to identify practices associated with positive learning outcomes, recurring limitations, and pedagogical implications for higher education. Following PRISMA-informed procedures, 44 empirical studies published between 2000 and 2025 were selected and thematically analyzed. The synthesis indicates that explicit, contextualized, and strategy-based instruction consistently supports vocabulary acquisition more effectively than decontextualized or incidental approaches, particularly in input-poor EFL contexts. The review further highlights the importance of addressing the depth of vocabulary knowledge and academic vocabulary demands in tertiary education. Based on the findings, the article outlines a research-informed framework for university-level EFL vocabulary instruction. Article visualizations: