Tlapanec (Mè’phàà) is known for its enigmatic tonal alternation in verb forms according to person and aspect-mode categories, in addition to suppletion and other segmental alternations. In this paper, we argue that the tonal alternations observed in Tlapanec regular agentive verbs can be straightforwardly accounted for by phonology, without resorting to any extreme abstractness: the lexical tones of the prefixes and the verb stems, with underspecification and floating tones, and cross-linguistically common tone processes such as tone spreading and floating tone docking. Such a phonological (or a morpheme-based) approach is contrasted with a word-based approach, where tonal alternations are viewed as inflectional classes. We show that the phonological approach is more adequate than a word-based approach.
