A phonological errors analysis of English consonants produced by Thai EFL undergraduate non-English major

Abstract

English pronunciation remains a persistent challenge for Thai EFL learners, primarily due to structural disparities between the Thai and English phonological systems. This study examines consonant production errors and the extent of L1 interference across word positions. This research aimed: 1) to analyse the pronunciation errors of English consonant sounds across three phonological positions-initial, medial, and final-among Thai undergraduate students who are non-English majors and study English as a foreign language; and 2) to investigate the effects of first language (L1) interference on the pronunciation of English consonant sounds in these three phonological positions. The sample consisted of second-year students from the Faculty of Education at Loei Rajabhat University in the academic year 2023 who were non-English majors. The participants were selected using cluster sampling from 15 separate programs, totaling 142 students. The research instrument was a set of vocabulary items covering 24 English consonant sounds, with one to six words selected for each consonant in each word position. Data were analysed using descriptive statistics. The findings revealed that lateral approximants (98.58%) and affricates (97.39%) constituted the most serious pronunciation difficulties, followed by fricatives (77.30%), indicating extensive first-language transfer effects. The predominance of sound substitution, devoicing, unaspiration, unreleased final stops, and vowel epenthesis demonstrates that the Thai phonological system strongly influences English consonant production across initial, medial, and final positions. These results highlight the need for explicit pronunciation instruction targeting English consonants that are absent or phonologically distinct from Thai, particularly lateral approximants, affricates, and fricatives.