Melodic tone in Bantu: overview

A fundamental notion of many suprasegmental theories such as Autosegmental Phonology is that of a " tone melody " , the idea that the tones on a word may be abstracted away from the phonemes that they are realized on. This allows the identification of a small number of tone patterns like H, L, HL, LH and LHL found in Mende nouns (Leben 1973, Goldsmith 1976). Such an analysis also explains patterns of verb inflection in Tiv, where verb tense-aspect is signalled by modifications of root tone whereby L roots have allomorphs like [ngòhòrò, ngòhórò, ngòhóró] 'accept', and H roots have the variants [yévèsè, yévésè, yévésé] 'flee' – stems may add L, HL or H, depending on inflectional form. This situation, where alternation in stem tone plays a central role in verb inflection , is quite widespread in Bantu, and is the focus of this volume. Indeed, to the best of our knowledge, such patterns are universal in those Bantu languages with tone, and are missing only in a handful of languages such as Swahili or Nya-kyusa that have no tone. Despite being ubiquitous in Bantu, we believe that the nature of these systems as a whole is not well understood, even though some specific systems are well-understood. Apart from the unfortunate fact that distinctive tone can still be left out of descriptions, investigation into grammatical tone is hampered by the lack of an investigative framework which informs the language-describer what data might be needed in such a study. A description that focuses on the wide range of tense, aspect, mood, polarity and clause-type factors, inter alia, which typically enter into verb inflection in Bantu is unlikely to simultaneously cover the relevant range of stems shapes for every inflectional form, along with sometimes relevant differences in subject and object prefixes. See Marlo (2013) for extensive discussion of numerous factors relevant to the study of verbal tone in Bantu, and Nurse (2008) for a study of tense and aspect in Bantu. The typical situation is that verb roots fall into one of two lexical classes, H, and L or toneless. Stems are composed of a root plus optional derivational affixes (" extensions "), terminating in an inflectional suffix. Extensions do not generally have distinctive underlying tone (it is sometimes thought that-u-'passive' and-i-'causative' may have had H tone, as in Kifuliiru (van Otterloo)), and the tonality