A morphophonological approach of vowels lengthening in Tagbana

In this article, vowel lengthening word internally in Tagbana, a Senufo language of Côte d’Ivoire is investigated. All vowels are underlyingly short, and all long vowels are the result of a lengthening process. Various lengthening processing are observed in Tagbana. (i) A lengthening due to the fusion of two independent morphemes, an aspect morpheme and a resumptive pronoun. (ii) Lengthening due intonation parameters where sentences last vowels are lengthening for interrogation purposes. See section 2.5 for these lengthening forms. (iii) Vowel lengthening due to the presence of two consonantal segments [l] and [r] in certain morphological environments. It is this late form of lengthening that attract my intention in this paper. It is proposed then that these consonantal segments have a double skeletal position which one is filled by the preceding vocalic segment. The consonants that trigger lengthening function as domain delimiters where both phonology and morphology play important roles. While [r] regularly triggers lengthening in Tagbana, some exceptions arise with [l]. A possible alternative is explored: It is proposed that lengthened vowels by lateral [l] get prominence during their pronunciation, as a consequence of lexical accent. Lengthening is accounted for by using locality conditions as proposed in Distributed Morphology.