Grammatical tone mapping in Ekegusii

Abstract A major issue in Bantu morphophonology is how to get the right tones in the right ‘cells’ in the verb paradigm. In many Bantu languages, grammatical tones are assigned to different positions in the verb stem depending on inflectional features of tense, aspect, mood (TAM), polarity and clause type: The same TAM may assign different tones (and different segmental allomorphs) in the affirmative vs. negative and in main vs. relative clauses. Although such ‘melodic tones’ (Odden & Bickmore 2014) are typically restricted to the verb stem (root + suffixes), often also the domain of vowel harmony and other segmental phonology, both the presence and mapping of grammatical tones within the stem cannot be determined without reference to the prefixal inflectional marking of subject, negation, TAM and object which precede the stem. In this article, we discuss three cases in Ekegusii, a Bantu language of Kenya, that require the stem-assigned grammatical tones to look ‘outward’ to morphological and phonological properties of such prefixes: (1) differential mapping according to whether the pre-stem tone-bearing unit is toneless, a derived H(igh) (from H-tone spreading), or underlyingly /H/ (Bickmore 1997, 1999); (2) presence of an object prefix in imperative and subjunctive forms and (3) initial/final tone agreement between the subject prefix and the final vowel of the verb (cf. Rolle & Bickmore (2022). We will show that Ekegusii provides extensive evidence that both the presence of grammatical Hs and their specific mapping, while targeting the stem (root + suffixes), must be ‘globally’ calculated on the basis of the entire morphosyntactic structure of the verb (including features exponed by prefixes).