ABSTRACT

Background: This research investigates the integration of Second Language Acquisition (SLA) theories within vocational English education, with particular emphasis on Krashen’s Input Hypothesis, Swain’s Output Hypothesis, and Vygotsky’s Sociocultural Theory. Given that vocational learners require language proficiency within specific professional contexts, SLA-informed instructional approaches, including task-based language teaching (TBLT) and communicative language teaching (CLT), are proposed to enhance practical language application in vocational settings. Objectives: The study seeks to examine the applicability of SLA theories to vocational English education, determine pedagogical strategies that effectively facilitate language acquisition among technical learners, and assess the challenges and best practices associated with implementing SLA-based methodologies within vocational learning environments. Methods: A Systematic Literature Review (SLR) was undertaken in accordance with the PRISMA framework. Relevant studies were sourced from JSTOR, Web of Science, and Google Scholar, applying inclusion criteria that emphasised peer-reviewed research, SLA pedagogy, and vocational English as a Second Language (ESL) contexts. Results: The review indicated that various SLA-based strategies, such as peer-assisted learning, sector-specific ESL training, professional development programmes, and multimodal instructional tools, were largely effective. Identified challenges encompassed inadequately trained teaching personnel, misalignment of curricula, and limited opportunities for learners to engage with authentic language exposure. Conclusion: The findings underscore the importance of targeted teacher training, policy-driven interventions, and the systematic incorporation of SLA theories and ESL practices into vocational curricula to enhance learners’ English language proficiency and workplace communication capabilities.