Towards a Unified Theory of Aspect in Nigerian Bantu-Adjacent Languages: Evidence from Igbo, Edo, and Yoruba

This study develops a unified theoretical account of aspect marking in three major Nigerian languages, Igbo, Edo, and Yoruba, situating the analysis within broader debates about the typology of aspect in Niger-Congo and making an original contribution to the formal semantic and morphosyntactic analysis of the aspectual domain. Existing descriptions of aspect in these three languages are largely language-specific and methodologically heterogeneous, making direct comparison difficult, while the theoretical modelling of their aspectual systems within current formal frameworks remains underdeveloped. The research adopts a formal linguistic methodology combining cross-linguistic elicitation, morphosyntactic paradigm analysis, and formal semantic composition drawing on Klein's event structure theory and Comrie's aspect typology. Primary data were elicited from 20 native speakers of each language through structured telic-atelic manipulation tasks, aspect coercion diagnostics, and embedded aspect interpretation tasks. The analysis identifies a tripartite aspectual domain including perfective-imperfective oppositions, habitual-progressive distinctions, and resultative constructions in all three languages, but documents significant parametric variation in the morphosyntactic realisation of these distinctions. A unified feature-geometric representation is proposed that captures the cross-linguistic commonalities and accounts for the observed parametric variation through a constrained set of morphosyntactic parameters. Keywords: aspect, Niger-Congo languages, Igbo, Yoruba, formal semantics.