Phonological constraints on English speech production among Kiswahili-speaking learners in Tanzanian technical education: A systematic review

Abstract

Oral English communication skills are essential for success in learning and subsequent employment in the Tanzanian vocational and technical education environment, where tasks require effective interactions. However, consistent problems with pronunciation amongst Kiswahili-speaking students reflect a significant lack in the body of research and practice related to teaching English pronunciation, specifically in the area of phonological constraints. This paper examines segmental, suprasegmental, and orthographic constraints that impact spoken English communication and assesses the effectiveness of pronunciation pedagogy in terms of Contrastive Analysis Theory (CAT) and Speech Learning Model (SLM). A comprehensive literature review was conducted based on the guidelines proposed by the PRISMA model. Scopus, Web of Science, and Google Scholar were used to collect relevant articles. The results of the research showed that phonological constraints remain a problem that impedes communication in English. Segmental pronunciation problems occur as a result of the substitution of sounds; suprasegmental constraints impact intelligibility through stress and intonation patterns. In turn, the orthographic constraint reflects the inconsistency between spelling and pronunciation. Each of these phonological constraints is related to first-language transfer, perceptual processing barriers, and insufficient attention to pronunciation instruction. The study shows that existing approaches towards developing English pronunciation skills are insufficient. Therefore, the author suggests adopting explicit pronunciation teaching and learning strategies, increasing teachers’ awareness of phonology-based instruction, and integrating both segmental and suprasegmental aspects of phonological awareness into classroom practices. Also, more attention should be paid to context-based strategies, including audio-visual means of instruction. Moreover, curriculum and educational policymakers should include pronunciation skills as part of communicative competence requirements.