Impact of Mother-Tongue Interference on English-Language Learning Among Senior Secondary Students in Enugu State, Nigeria

Abstract

Purpose. This study examined the impact of mother-tongue interference on English-language learning among senior secondary students in Enugu State, where Igbo–English contact is a daily condition of schooling and English remains the language of instruction, examination, and certification. Methodology. Interference was treated as three related constructs, phonological, syntactic, and lexical, anchored in the contrastive analysis hypothesis, error analysis, and interlanguage theory. A multistage sample of 360 SS2 students was drawn from public and private schools in Enugu East, Nsukka, and Awgu education zones. English learning was indexed by a 50-item achievement test. Cronbach’s alpha ranged from .78 to .86. Findings. Phonological interference correlated most strongly with achievement (r = −.42), followed by syntactic (r = −.38) and lexical interference (r = −.27). The three interference scores explained an additional 22% of variance in achievement after gender, school type, and home-language use were controlled (final R² = .29). Public-school students reported higher interference and lower achievement than private-school students (d = 0.85 and 0.75). Originality. The study provides a zone-level quantitative account that separates phonological, syntactic, and lexical interference, reports reliability for each construct, and estimates unique effects on a common achievement test among Igbo–English bilinguals in Enugu State. Research implications. The findings support targeted oral-English instruction, contrastive grammar teaching, and a policy that treats Igbo as a resource rather than as a defect to be punished.