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The Korean Association for the Study of English Language and Linguistics
[ Article ]
Korea Journal of English Language and Linguistics - Vol. 26, No. 0, pp.215-234
ISSN: 1598-1398 (Print) 2586-7474 (Online)
Print publication date 28 Feb 2026
Received 26 Dec 2025 Revised 15 Jan 2026 Accepted 16 Jan 2026
DOI: https://doi.org/10.15738/kjell.26..202602.215

Effects of Fluency on the Consistency and Contrast of English Vowel Production in Korean Elementary School Students

Soyoung Yi ; Hyunsong Chung
(First author) MA Student, Department of English Education Korea National University of Education 250 Taeseongtabyeon-ro, Gangnae-myeon, Heungdeok-gu, Cheongju-si, Chungbuk, Korea, Tel: +82-43-230-3554 200811019@daum.net
(Corresponding author) Professor, Department of English Education Korea National University of Education 250 Taeseongtabyeon-ro, Gangnae-myeon, Heungdeok-gu, Cheongju-si, Chungbuk, Korea, Tel: +82-43-230-3554 hchung@knue.ac.kr


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This is an open-access article distributed under the terms of the Creative Commons License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The present study examines how fluency relates to (i) within-category consistency and (ii) between-category contrast in English vowel production by Korean elementary school learners. We analysed both reading and spontaneous utterances produced by 45 male and 49 female students across four fluency levels. Vowel consistency was assessed using compactness scores (ellipse area in the F1–F2 space), and vowel contrast was assessed using Pillai scores derived from MANOVA for six vowel contrasts. The results indicate that vowel compactness is strongly structured by vowel category and shows no reliable effect of fluency for either gender, whereas vowel-contrast distinctness increases with fluency at the highest level (F05). These findings suggest that fluency-related improvement in vowel production is expressed primarily through enhanced contrastive organisation rather than through reduced within-category dispersion. Accordingly, pronunciation instruction may be more effective when it emphasises contrastive learning rather than general articulatory ‘accuracy’.

Keywords:

vowel formant, compactness score, Pillai score, pronunciation

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