Beyond the Classroom: Sociolinguistic Factors as Predictors of Vocabulary Breadth in Tanzania’s Diverse Linguistic Landscape

This paper examines the impact of sociolinguistic factors on vocabulary breadth among secondary school learners in Tanzania. While research on sociolinguistics and language acquisition exists, the interaction between sociolinguistic factors and English vocabulary breadth in Tanzania’s educational context remains underexplored. This is significant given that English, a foreign language spoken by a minority, is the medium of instruction from secondary school onwards in a multilingual country with over 150 ethnic community languages (ECLs), and Kiswahili is spoken by the majority. The study addresses: How do sociolinguistic factors influence English vocabulary breadth among learners in Tanzania’s diverse linguistic landscape? A convergent parallel mixed-methods design was adopted to triangulate quantitative and qualitative data. Using stratified random sampling, the New Vocabulary Levels Test was administered to 320 Form 3 and 4 students from eight secondary schools in Dodoma, and interviews were conducted with the eight English teachers to provide deeper insight. Multiple regression and thematic analyses revealed that sociolinguistic factors significantly influenced vocabulary breadth. Learners who used English at home or in class, interacted with English-speaking peers, started learning English in kindergarten, and had parents with at least Form 4 education had broader vocabularies. Findings suggest that sociolinguistic factors play a crucial role in vocabulary development. Policymakers should enhance structured English exposure beyond the classroom and adopt additive bilingual approaches that consider learners’ language ecology. This study contributes to understanding the interplay between sociolinguistic factors and vocabulary mastery in a diverse linguistic setting and recommends further research on this interaction.