Enhancing TOEIC Listening Performance Through Explicit Lexical Stress Instruction

Abstract

English listening comprehension remains a significant challenge for many EFL learners, particularly in high-stakes testing contexts such as the TOEIC, where rapid speech and prosodic features can hinder understanding. Among these features, lexical stress plays a crucial role in speech perception, yet it is often underemphasized in instruction. This study examined the impact of explicit lexical stress instruction on the TOEIC Listening performance of Thai engineering undergraduates. Seventy-three fourth-year mechanical engineering students participated in a 15-week intervention that integrated pronunciation-focused instruction with TOEIC-style listening practice. Data included a 50-item lexical stress pre/posttest, a mock TOEIC Listening pre/posttest, and a post-instruction focus group interview. Quantitative analyses revealed substantial improvement in stress identification accuracy, with a mean gain of 12.56 points (p < .001). TOEIC Listening scores also increased significantly. Qualitative results indicated that lexical stress training enhanced general listening comprehension, facilitated vocabulary retention, improved recognition of noun–verb stress contrasts, and strengthened learners’ confidence and exam readiness. Participants reported that accurate stress practice enhanced their listening ability, “enabling more efficient segmentation of natural-speed input. Thematic vocabulary grouping and AI-assisted pronunciation tools further supported learning. The findings confirm that lexical stress awareness plays an important role in improving English listening comprehension and high-stakes test outcomes.