(ProQuest: ... denotes formulae omitted.)1. IntroductionThis paper2 accounts for the numerous surface tonal melodies found on the verb in Babanki, a Grassfields Bantu language of northwestern Cameroon. An examination of the verb system reveals that, depending on the construction type, up to three tonal patterns may be found on both low and high tone verbs (See §3.3 where it is shown that Babanki verbs have two lexical tones: high and low). An underlying high tone may surface normally as high, but unexpectedly as low, or falling while underlying low tones surface as high, falling, but normally as low. For this reason the low tone verb can have a L(L), HL, or even H(H) surface melody while the high tone verbs can be L(H), HL, or H(H). Sometimes, a high tone can be downstepped while a low tone can undergo upstep. Accounting for these melodies in order to reconstruct the underlying forms is necessary for a proper understanding of Babanki verb tone in particular and the tonal system of Centre Ring Grassfields Bantu languages in general. This is so because most of the work on tone in Babanki has focused on the nominal system (Hyman 1979, 1980; Akumbu 2011). A treatment of verb tone will therefore provide a more complete picture of Babanki tone and also lay the groundwork for analyzing the tone systems of the other languages in the group. This paper demonstrates that five tone rules (Downstep, Tone Docking, High Tone Spread, Low Tone Spread, and Upstep) and one segmental rule (Schwa Insertion) are necessary to account for the apparently complex tonal system of Babanki verbs. The theoretical frameworks used in the analyses are Register Tier Theory (RTT) and Autosegmental Phonology (AP). This paper is structured as follows: An overview of RTT is given in §2 and the Babanki verb system is introduced in §3 while §4 contains a presentation of tense, aspect and mood. The phonological processes that are recurrent in the verb system are discussed in §5. An expansion of the discussion to verbal reduplication is found in §6, which is followed by a conclusion.2. An overview of register tier theoryRegister Tier Theory (RTT) (Inkelas 1987; Inkelas et al. 1987; Snider 1988, 1990, 1999; Akumbu 2011) recognizes the following autosegmental features and tiers: the register features h and l on a REGISTER TIER, the tonal features H and L on a TONAL TIER, a TONAL ROOT NODE TIER (TRN), and a TONE-BEARING UNIT TIER (TBU). These tiers are geometrically arranged according to the configuration in Figure 1 taken from Snider (1999: 23).The geometry in Figure 1 and the features in Figure 2 make it possible to specify up to four logically possible tonal distinctions, namely, a high tone on a high register, a high tone on a low register, a low tone on a high register, and a low tone on a low register. The register feature of any given TBU is specified in relation to that of the preceding register. The register of the initial TBU for its part is construed to be higher than or lower than the reference point that native speakers usually have in mind when beginning an utterance. Secondly, the tonal feature associated to any given TBU specifies whether the tone is low or high in relation to the current register. RTT is used in this paper to insightfully explain the tonal processes, given that within this theoretical model features on each tier can behave independently of one another.3. The verbIn this section the structure of the Babanki verb is shown. The section comprises a presentation of the verb root, verbal extensions, and tone groups, which are relevant to the discussion of verb tone in the language.3.1. Verb root. According to Akumbu & Fogwe (2012) only one-syllable roots are attested in Babanki except when there is verbal reduplication. The verb roots that appear to have two syllables always have a CV ending, which can be interpreted as an extension (see §3.2). Nevertheless, there are formal extensions that can be considered part of the root. …