# The noncausal/causal alternation in the Western Serengeti languages

Antti Laine

University of Helsinki

Rasmus Bernander

University of Helsinki; University of Gothenburg

Lotta Aunio

University of Helsinki

## ABSTRACT

This paper takes a look at the noncausal/causal alternation in a sample of about 30 verb pairs in the Western Serengeti languages (WS) Ikoma, Ishenyi, Nata and Ngoreme, spoken in the Mara region of Tanzania. Based on the data presented, these languages can be said to favour a strategy of causativization, i.e. deriving the causal verb from a noncausal base, in coding this alternation. In a preliminary cross-linguistic comparison, this preference for causativization seems to be stronger than in other (Tanzanian) Bantu languages for which data is available. The data also shows that the reflexive prefix is used more often than the neuter suffix in anticausative pairs. While the latter has a widespread use across Bantu languages to derive noncausal verbs, it is unproductive in WS.

## KEYWORDS

Bantu, micro-variation, noncausal/causal alternation, verbal derivation

## RÉSUMÉ

Cet article examine l'alternance non causal/causal dans quatre échantillons de 30 paires de verbes chacun provenant des langues sérengéti occidentales suivantes : l'ikoma, l'ishenyi, le nata et le ngoreme, toutes parlées en Tanzanie dans la région de Mara. D'après les données considérées, il appert que les quatre langues en question tendent à favoriser une stratégie causative consistant à dériver des verbes causals à partir de verbes de base non causals. Cette première étude comparative semble montrer que les langues ici étudiées ont davantage recours à cette stratégie causative que les autres langues bantoues de Tanzanie pour lesquelles on dispose de données. En outre, on peut également observer que le préfixe du réfléchi est plus souvent employé que le suffixe neutre dans des pairs anticausatifs. Alors que ce même suffixe neutre est fréquemment employé en bantou pour dériver des verbes non causals, il n'est pas productif dans les langues sérengéti occidentales.

## MOTS CLÉS

alternance non causal/causal, bantou, dérivation verbale, microvariation
# 1. INTRODUCTION

In this paper, we present data on noncausal/causal verb pairs in the Western Serengeti languages (WS) and contribute to the analysis of formal strategies deployed in expressing noncausal/causal events in WS. As WS comprises several language varieties, we work from a comparative perspective and discuss micro-variation within WS wherever relevant differences are attested. Furthermore, we compare the WS data to other Bantu languages as well as to non-Bantu ones.

In this introductory section, we provide some background to the Mara region and its languages, and introduce the key concepts related to the noncausal/causal alternation. In Section 2, we present the WS data and the morphological means of derivation utilized to code the alternation. Section 3 discusses the WS data in comparison to other Bantu languages, and the closing Sections 4 and 5 are devoted to a wider typological outlook and, finally, some concluding remarks.

## 1.1 The Western Serengeti languages

WS, spoken in the Mara region of Tanzania, is a group of neighbouring and closely-related of Bantu languages in the Mara (JE40) subgroup of Lacustrine Bantu (Schoenbrun 1990; Aunio et al. 2019; Roth & Gibson 2019). The varieties of WS are Ngoreme (ngg; JE402) and Ikoma, Ishenyi and Nata (all jointly coded as *ntk*; JE45). The Mara region is situated between Lake Victoria to the west and the Serengeti National Park to the east, and bordering Kenya to the north (see Map 1). The region is linguistically diverse, having a cornucopia of Bantu varieties but also Nilotic languages (Luo, Datooga, formerly Maa), along with a putative previous presence or influence of Cushitic (Heine 1976; Schoenbrun 1990 and 1994; Shetler 2003).

The WS varieties exhibit a close genetic relation based on their lexicon (Hill et al. 2007), but there is a significant amount of structural (micro-)variation in different domains of their grammars (see e.g. Aunio 2017; Roth & Gibson 2019; Bernander & Laine 2020; Bernander et al. accepted), in particular in their tonology, TAM systems and various more complex morphosyntactic constructions such as existentials or relative clauses. WS has, as is typical for East Bantu languages, an elaborate noun class system with up to 20 noun classes (with some minor variation in the noun class inventory and productivity) and is agglutinative with complex verbal morphology.

## 1.2 The noncausal/causal alternation

The noncausal/causal alternation is a semantic notion dealing with the relationship between verb pairs that express the same basic event but with a different number and different types of participants. A noncausal verb denotes a one-participant event, while the corresponding causal one adds another participant, one that causes the action to take place. Cross-linguistically, several different strategies to code these alternations are found, and they can be organized and accounted for in different ways (see e.g. Haspelmath 1993; Nichols et al. 2004; Creissels, this issue). Here, we use the taxonomy also used by Dom et al. (2021; ultimately from Haspelmath 1993), with the following strategies for distinguishing causal and noncausal events from each other.

First, the **causative strategy (C)** refers to a situation where the noncausal verb is basic and the causal verb is derived, that is, something is added to the verb to make it causal. In the **anticausative strategy (A)** we have the opposite situation, where the noncausal verb is derived via an intransitiveizer of one type or another, and the causal verb is basic. The **equipollent strategy (E)** is, in a way, a combination of the first two whereby both verbs are derived. Note that while the noncausal and causal verbs often contain a common root, it is not strictly necessary for one to be derived from the other; see Introduction, this issue.

The last two strategies are termed **labile (L)** and **suppletive (S)**; labile verbs can act as both causal and noncausal ones without any derivation at all, and suppletive verb pairs include two entirely unrelated roots with neither one derived from the other (though one or both members might have derivational morphology marking it as intransitive or transitive).
<figure><img src="image_1.png" /><figcaption>Map 1 — *The Mara languages and their neighbours*
© Monika Feinen Topographic Data © OpenStreetMap contributors</figcaption></figure>

As we see in the following Section 2, WS makes most use of the causative strategy. Anticausative and equipollent strategies also feature prominently in the dataset. Lability and suppletion are scarcely attested in our data, though (partly tentative) examples of both are provided.

## 2. WESTERN SERENGETI DATA

### 2.1. General overview

Our study is based on Haspelmath's (1993: 96-97) list of 31 verb pairs used in his typological study of what he terms the “inchoative/causative” alternation. The verb pairs, along with elicited examples of their use, have been collected from all four WS varieties. A list of all verbs along with the full set of WS verb pairs can be found in the Appendix. A few verb pairs have been left out from our quantitative analyses due to inconclusive data (cf. Dom et al. 2020; Yoneda 2014 and this issue for similar problems in other closely related Bantu languages).<fnref n="1" />

Table 1 shows a general overview of the WS data. The number of verb pairs counted for each variety are in the first numerical column, followed by the number of times anticausative, causative, equipollent, labile and suppletive strategies are attested. Finally, on the furthest right, we have the ratio of verb pairs with anticausative strategies to ones with causative strategies. As mentioned above, we see at first glance from the table that the causative strategy far outnumbers the others, with between 15

<footnote n="1">1. We have no good data for ‘dissolve’ in any WS variety. ‘finish’ has been left out from our counts due to the highly variable results, though it is discussed separately below. The equivalents of ‘rise, raise’ and ‘improve’ have also not been counted, as the data points are rather inconclusive in terms of comparable semantics. Finally, ‘go out/put out’ in Ishenyi as well as ‘sink’ in Ngoreme have been left out, resulting in a difference in sample sizes between varieties.</footnote>
and 18 instances, depending on language variety. The number of pairs with anticausative and equipol-
lent strategies is far lower, and the amount of labile and suppletive verbs is smaller still, with lability
being unattested in Ikoma, Nata and Ngoreme, and only one labile pair attested in Ishenyi.

<table><caption>Table 1 — Comparative table of expression types in WS</caption><thead><tr><th></th><th>Verb pairs</th><th>A</th><th>C</th><th>E</th><th>L</th><th>S</th><th>A/C ratio</th></tr></thead><tbody><tr><td>Ikoma</td><td>27</td><td>4</td><td>17</td><td>5</td><td>0</td><td>1</td><td>0.23</td></tr><tr><td>Ishenyi</td><td>26</td><td>5</td><td>16</td><td>3</td><td>1</td><td>1</td><td>0.31</td></tr><tr><td>Nata</td><td>27</td><td>4</td><td>17</td><td>5</td><td>0</td><td>1</td><td>0.23</td></tr><tr><td>Ngoreme</td><td>26</td><td>4</td><td>16</td><td>4</td><td>0</td><td>2</td><td>0.25</td></tr></tbody></table>

## 2.2 Morphological strategies

All surveyed noncausal/causal verb pairs in WS are formed synthetically by verbal affixes. This is expected, given that the use of affixes is the most widespread means for verbal derivation across Bantu (see e.g. Schadeberg & Bostoen 2019). As is typical in the derivational systems of most Bantu languages, verbal derivation in the WS varieties operates mainly through suffixes. There is one prefix, however, that is typically used to code the reflexive. The suffixes that are relevant for our present purposes are the causative, the neuter, the separative — the last of which has both a transitive and intransitive variant — and the passive. All of these functions are marked by reflexes of reconstructed Proto-Bantu forms (Schadeberg & Bostoen 2019: 173), and we are thus dealing with typical Bantu morphemes, though some of them have uncanonical formal properties (see below). The Proto-Bantu reconstructions along with their WS reflexes are shown in Table 2.

<table><caption>Table 2 — Affixes involved in WS noncausal/causal alternations</caption><thead><tr><th>Prefix</th><th></th><th>Proto-Bantu</th></tr></thead><tbody><tr><td>Reflexive</td><td><i>i-</i></td><td>*ji-</td></tr><tr><td>Suffixes</td><td></td><td></td></tr><tr><td>Causative</td><td><i>-i</i></td><td>*-i/-ici</td></tr><tr><td>Neuter</td><td><i>-Ek</i></td><td>*-ik</td></tr><tr><td>Separative tr.; intr.</td><td><i>-Ur</i>; <i>-Uk</i></td><td>*-ul; -ok</td></tr><tr><td>Passive</td><td><i>-u</i></td><td>*-u/-ibu</td></tr></tbody></table>

### 2.2.1 Causative strategy

The verb pairs with the causative strategy are quite straightforward: they all make use of the caus-
ative suffix, as shown in the Ikoma infinitive pairs in (1). For example, to the stem *-booka* ‘to wake
up (intr.)’, with the default final vowel *-a*, the causative suffix is added to derive the corresponding
transitive causal stem: *-booki*. Sentential examples with fully inflected verbs are shown in (2).

(1) Ikoma

<table><tr><td>a. <i>koβóóka</i></td><td>— <i>koβóóki</i></td></tr><tr><td>ko-βook-a</td><td>ko-βook-i</td></tr><tr><td>INF-wake_up-FV</td><td>INF-wake_up-CAUS</td></tr><tr><td>‘to wake up (intr.)’</td><td>‘to wake up (tr.)’</td></tr></table>
<table><tr><td>b. <b>kujáája</b></td><td>— <b>kujááji</b></td></tr><tr><td>ku-jaaj-a</td><td>ku-jaaj-i</td></tr><tr><td>INF-melt-FV</td><td>INF-melt-CAUS</td></tr><tr><td>'to melt (intr.)'</td><td>'to melt (tr.)'</td></tr></table>

(2) Ikoma

a. *omóóna* aakáβooka
o-mo-Vna a-Vká-βook-a
AUP-1-child SM1-NUCL<fnref n="2" />-wake_up-FV
'The child has woken up.'

b. ookáβooki omóóna
o-Vká-βook-i o-mo-Vna
SM2SG-NUCL-wake_up-CAUS AUP-1-child
'You have woken up the child.'

The form of the causative suffix in WS is uncanonical from a Bantu perspective. Typically in Bantu languages, the inflectional final vowel -a follows the causative suffix, often resulting in glide formation. In WS, however, the causative verbs end in the simple suffix -i, as consonant-glide combinations are not allowed in final syllables. The suffix is a reflex of the PB short causative suffix, which was used after consonant-final roots (Schadeberg & Bostoen 2019: 174). The suffix *-ici*, shown in Table 2, was used after vowel-final roots; reflexes of this longer form are few and far between in WS due to a scarcity of suitable roots, but it is found as -i/f/ at least in the Ikoma verb stem -γw-i/f-a 'drop', derived from -γo 'fall'.

A corresponding peculiarity is seen with the passive suffix, which is just a final -u in WS instead of a labialization of the final consonant followed by -a.<fnref n="3" />

The WS causative suffix is involved in some interesting vowel harmony processes. WS features unusual ATR harmony phenomena, which have been described for Ikoma by Higgins (2012); similar though not always identical harmony systems are at play in the other WS varieties as well. The picture is further complicated by the instability of the Ishenyi and Ngoreme vowel systems in general — both seem to be transitioning from seven to five phonological vowels, leaving behind residual harmony effects and elusive allophonic variations. Note that ATR distinctions have been consistently neutralized in Ngoreme verb roots (though not in nouns).

Focusing on the causative suffix and the stable Ikoma system, as per Higgins's (2012: 200-207) description, the suffix (with a +ATR /i/) raises a -ATR mid-vowel in the root to +ATR: /ɛ > e/.<fnref n="4" /> In other words, the ATR value spreads leftwards from the suffix to the root, as in (3).<fnref n="5" />

<table><tr><td>(3) Ikoma</td><td></td></tr><tr><td>γusééma</td><td>— yuséémi</td></tr><tr><td>γu-sɛɛm-a</td><td>γu-sɛɛm-i</td></tr><tr><td>INF-begin-FV</td><td>INF-begin-CAUS</td></tr><tr><td>'to begin (intr.)'</td><td>'to begin (tr.)'</td></tr></table>

<footnote n="2">2. The “nucleative”, glossed NUCL, is an elusive TAM form found in Ikoma, Ishenyi and Nata. The term was coined by Roth (2018) in his description of aspect in Ikoma and Ngoreme. The nucleative functions as a pseudo-perfective/progressive, with readings dependent on the verb’s lexical aspect, while also involving evidentiality. For a full discussion of the nucleative in Ikoma, see Roth (2018: 103-109).</footnote>

<footnote n="3">3. There is also a “long” passive suffix -eβu/-iβu in WS, a reflex of the Proto-Bantu reconstruction *-ibo and used analogously to the long causative.</footnote>

<footnote n="4">4. /ɔ/ in the root is also raised by causative -i, but it does not fully merge with /o/.</footnote>

<footnote n="5">5. Note that, in a typologically unusual state of affairs, the vowel in the infinitive prefix is dissimilated — rather than assimilated — from /o/ to /u/ to prevent two mid-vowels of different ATR values from appearing in consecutive syllables. This dissimilation affects all mid-vowel prefixes in WS, and in this case, the resulting form of the infinitive is preserved even in the causative stem with the raised mid-vowel.</footnote>
Both Nata and Ngoreme pattern with Ikoma in having mid-vowel raising. The Ishenyi causative suffix on the other hand has more complex effects on the vowels, but these effects are not yet fully understood. It is important to realize that the Ishenyi vowel system is the least consistent within WS, with both inter- and intra-speaker variation. The vowel allophones are also more variable than in the other varieties, with the occasional conflation of the +ATR mid-vowels [e o] with the -ATR high vowels [i u]. Despite the variation, these patterns are consistent in some constructions. One such case is the influence of the causative suffix -i (which is invariably +ATR /i/ in all of WS) on the vowels of verb roots, namely a lowering of first degree vowels in verb roots to [i ~ e] or [u ~ o]. The details of patterns of this type and other questions regarding Ishenyi vowels warrant further research. For more, see Laine *et al.* (2022).

### 2.2.2 Anticausative strategy

The second most common strategy in WS is the anticausative one, and it subsumes four morphological derivational patterns, shown in Table 3. This contrasts with the single suffix used in the causative strategy. The following meanings have anticausative verb pairs in one or more WS varieties: ‘close’, ‘break’ and ‘change/turn’ in all WS varieties; ‘gather’ for all varieties except Ngoreme (where it is equipollent; see below); ‘rock/sway’ only in Ngoreme; and, finally, ‘sink’ in Ishenyi.<fnref n="6" />

<table><caption>Table 3 — Breakdown of morphological means of deriving anticausative verbs</caption><thead><tr><th>Variety</th><th>Total</th><th>REFL</th><th>NEUT</th><th>PASS</th></tr></thead><tbody><tr><td>Ikoma</td><td>4</td><td>3</td><td>1</td><td>0</td></tr><tr><td>Ishenyi</td><td>5</td><td>4</td><td>1</td><td>0</td></tr><tr><td>Nata</td><td>4</td><td>2</td><td>1</td><td>1</td></tr><tr><td>Ngoreme</td><td>4</td><td>3</td><td>1</td><td>0</td></tr></tbody></table>

As seen from the table, the most frequently attested derivational morpheme in anticausative verb pairs is the reflexive prefix, as shown in (4).

(4) Ishenyi

<table><tr><td>γwíkuma</td><td>—</td><td>yokúma</td></tr><tr><td>γw-i-kum-a</td><td></td><td>γo-kum-a</td></tr><tr><td>INF-REFL-gather-FV</td><td></td><td>INF-gather-FV</td></tr><tr><td>‘to gather (intr.)’</td><td></td><td>‘to gather (tr.)’</td></tr></table>

Interestingly, the Ikoma and Nata verbs for ‘gather’ in our database have a combination of the reflexive prefix *i-* with the associative (or reciprocal) suffix *-an:* γw-*i*-kom-*an*-a ‘gather (intr.)’ from γo-kom-a ‘gather (tr.)’, as shown in (5).

(5) Ikoma

<table><tr><td>a-βá-áto</td><td>βa-ay-i-kom-an-a</td></tr><tr><td>a-βa-Vto</td><td>βa-Vγá-i-kom-an-a</td></tr><tr><td>AUP-2-person</td><td>SM2-NUCL-REFL-gather-ASS-FV</td></tr><tr><td colspan="2">‘The people have gathered (there).’</td></tr></table>

<footnote n="6">⁶. ‘sink (intr.)’ in Ishenyi uses the reflexive prefix *i-*: kw-*i*-méri. The causative suffix is lexicalized to the root and remains in place in the noncausal verb. The pair is thus counted as anticausative and not equipollent; see below for more examples and discussion.</footnote>
The presence of the suffix -an in Ikoma and Nata can be explained by the associative semantics of the event denoted by the intransitive verb, that is, ‘gather (intr.)’ meaning ‘come together’. As our Ikoma and Nata data is limited, we cannot exclude the possibility that these two languages also have a reflexive-only verb form for ‘gather’, like Ishenyi in (4).

The neuter suffix is used in only one pair in all of the varieties, namely the verb ‘break’, e.g. Ikoma -βun-ɛk-a/-βun-a ‘break-NEUT-FV/break-FV’. The neuter suffix in WS is confined to verbs of destruction like ‘break’, which has been described as a widespread semantic tendency in Bantu languages (cf. Schadeberg & Bostoen 2019: 179). However, in WS the neuter suffix does not have any of the extended functions described in some languages, such as passive voice or stimulus-oriented perception (Dom et al. 2016: 132-134; 2018: 168; Chavula 2018; Bernander 2018). The reflexive prefix, on the other hand, has developed into a general intransitivizer, extending its functions beyond only the reflexive into middle voice (see Dom et al. 2016; 2018 for further elaboration on the complex linguistic concept of middle voice from a Bantu perspective; Ngwasi 2021 for more on the functions of reflexives in Tanzanian Bantu languages). The functional expansion of the reflexive prefix into the middle voice has decreased the productivity of two intransitivizing suffixes, namely, the neuter and intransitive separative.

Additional examples from Ngoreme of the anticausative use of the reflexive prefix and the neuter suffix are shown in Table 4.

<table><caption>Table 4 — Reflexive and neuter examples from Ngoreme</caption><thead><tr><th>Morphological pattern</th><th>Meaning</th><th>Noncausal</th><th>Causal</th></tr></thead><tbody><tr><td rowspan="3">Reflexive <i>i</i>-</td><td>‘close (it.)/(tr.)</td><td><b>-i-jiγar</b><sup>-7</sup></td><td><b>-iγar</b>-</td></tr><tr><td>‘rock (intr.)/(tr.)’</td><td><b>-i-hintʃi</b></td><td><b>-hintʃi</b></td></tr><tr><td>‘change (intr.)/(tr.)’</td><td><b>-i-fɔɔri</b><br><b>-i-hɔntʃɔra</b></td><td><b>-fɔɔri</b><br><b>-hɔntʃɔr-</b></td></tr><tr><td>Neuter -ɛk</td><td>‘break (intr.)/ (tr.)’</td><td><b>-tɛn-ɛk-</b></td><td><b>-tɛn-</b></td></tr></tbody></table>

Note that the causal verbs -hintʃi ‘rock’ and -fɔɔri ‘change’ have a lexicalized causative suffix -i. The suffix has become part of the stem, as it remains in place in the derived noncausal verbs -i-hintʃi and -i-fɔɔri. These verb pairs are thus not counted as equipollent. There are historical implications here, of course. These verb pairs are, likely, cases of historical causativization (nC > C), with causative derivation from a base verb that has since become obsolete.

One anticausative verb pair in Nata, illustrated in (6), has the noncausal verb derived from the causal verb through the addition of both the applicative and the passive suffixes.

(6) Nata

<table><tr><td><i>kwíγarɛru</i></td><td>—</td><td><i>kwíγara</i></td></tr><tr><td><i>kw-iyar-ɛr-u</i></td><td></td><td><i>kw-iyar-a</i></td></tr><tr><td><i>INF-close-APPL-PASS</i></td><td></td><td><i>INF-close-FV</i></td></tr><tr><td>‘to close (intr.)’</td><td></td><td>‘to close (tr.)’</td></tr></table>

There are some examples in our database that indicate that the passive suffix is used to code a potential passive function, a grammatical function that is coded by the neuter suffix in other Bantu languages (Dom et al. 2016: 133). This is illustrated in examples (7) and (8), with verbs from outside the noncausal/causal sample.

<footnote n="7">7. In this verb, the reflexive prefix *i-* combines with a vowel-initial stem *iyar*. The heteromorphemic sequence of identical vowels is realized as /iji/, with a palatal approximant in between the vowels.</footnote>
(7) Ikoma: -ra 'eat'

eriikóroßese rekeeré rerarééβu

e-rii-koroßese re-keere re-ra-r-eβu

AUP-5-fruit SM5-PERS SM5-PROG-eat-PASS

'The fruit is still edible.'

(8) Ngoreme: -sɔma 'read'

e-γi-táβɔ kí-nɔ γe-eyu-sɔm-u

e-γi-taβɔ ki-nɔ γe-eyu-sɔm-u

AUP-7-book 7-REL SM7-IPFV-read-PASS

'the book which is readable, the readable book'

The passive suffix is also attested on noncausal members of some equipollent pairs, which we discuss in the following section (§2.2.3).

### 2.2.3 Equipollent strategy

The final major strategy, the equipollent one, also presents a somewhat variable picture in the sense that it includes multiple different morphological alternations. Table 5 gives an overview of the four different morphological alternations that are attested in all four WS languages, illustrated with the 5 equipollent pairs from Ikoma: The first morphological alternation has the intransitive separative and the causal one has the causative. In the second morphological alternation, the passive is used for the noncausal verb, and the third morphological alternation involves the neuter suffix for the noncausal verb. In all three of these alternations, the causal verb is derived with the causative suffix -i. The final morphological alternation makes use of both the transitive and intransitive variant of the separative. Note that we have counted 0.5 cases, i.e. half points, where there are synonymous verbs with different derivational strategies (following Haspelmath 1993; Creissels, this issue).

We can see in the Ikoma examples in Table 5 that the morphological causative is used with the causal member in most of the equipollent pairs. As the suffix is also used for the predominant causativization strategy in WS, it features prominently in the noncausal/causal data.

<table><caption>Table 5 — Equipollent strategies in Ikoma</caption><tr><td>-Uk- vs. -i<br>SEP VS. CAUS</td><td>1</td><td>'boil'</td><td>-hiif-ok-a</td><td>-hiif-i</td></tr><tr><td>-u vs. -i<br>PASS VS. CAUS</td><td>1</td><td>'sink'</td><td>-mer-u</td><td>-mer-i</td></tr><tr><td>-Ek- vs. -i<br>NEUT VS. CAUS</td><td>1.5</td><td>'destroy'</td><td>-sar-ɛk-a</td><td>-sar-i</td></tr><tr><td></td><td></td><td>'split'</td><td>-at-ɛk-a</td><td>-at-i</td></tr><tr><td>-Uk- vs. -Ud-<br>SEP (intr.) vs. SEP (tr.)</td><td>1.5</td><td>'split'</td><td>-tand-uk-a</td><td>-tand-ur-a</td></tr><tr><td></td><td></td><td>'open'</td><td>-iy-ok-a</td><td>-iy-or-a</td></tr></table>

The equipollent data exhibits micro-variation between the WS varieties. While the meaning 'sink' has an equipollent verb pair in Ikoma, Ishenyi has an anticausative pair *kw-i-méri/ko-méri*, with the causative suffix lexicalized onto the verb root. In Ikoma and Nata, the noncausal verb is formed with the passive, -mer-u alternating with the segmentable causative suffix -i on the causal verb -mer-i; if the causative was lexicalized and retained as part of the stem for the noncausal verb, the stem would be vowel-final and the longer form of the passive, -(i)βu, would be used. Another example of variation
is seen with the verb pairs for ‘gather’. Ngoreme has an equipollent pair with a reflexive/causative alternation, i.e. -i-kɔ́man-a/-kɔ́man-i, whereas Ikoma, Ishenyi and Nata all have anticausative pairs, e.g. -i-kóm-an-a/-kóm-a in Ikoma and Nata.

### 2.2.4 Suppletion and lability

As mentioned above in Section 1.2, labile and suppletive strategies are uncommon in WS. As expected from cross-linguistic patterns, suppletion is found in the pair ‘die/kill’, e.g. -ku/-ita ‘die/kill’.<fnref n="8" /> More surprisingly, there is another suppletive pair found in Ishenyi: -sira/-mara ‘finish (intr./tr.)’, exemplified in context in (9).<fnref n="9" />

#### (9) Ishenyi

##### a. umɔ́ɔ́ka ɔ́nɔ̈ ookámara yusíra

<table><tr><td>u-m-ɔ̈ka</td><td>ɔ̈-nɔ̈</td><td>o-Vká-mä-a</td><td>γu-sï-a</td></tr><tr><td>AUP-3-year</td><td>3-PROX.DEM</td><td>SM3-NUCL-finish-FV</td><td>INF-finish-FV</td></tr></table>

‘This year has already finished.’

##### b. umɔ́ɔ́ka ɔ́nɔ̈ tookámara yoyumára<fnref n="10" />

<table><tr><td>u-m-ɔ̈ka</td><td>ɔ̈-nɔ̈</td><td>to-Vká-mä-a</td><td>γo-γu-mä-a</td></tr><tr><td>AUP-3-year</td><td>3-PROX.DEM</td><td>SM1PL-NUCL-finish-FV</td><td>INF-OM3-finish-FV</td></tr></table>

‘We have already finished this year.’

Note that -mara ‘finish’ has also grammaticalized into an auxiliary denoting the phasal polarity concept of ‘already’, as demonstrated by both examples in (9). This is a trajectory of grammaticalisation shared across WS (Bernander et al. 2021 and forthcoming). Apart from this additional function of -mara, some striking micro-variation is found across WS in the way this verb pair functions. While Ishenyi is a clear-cut case of suppletion, a verb -sira ‘end’ is also found in Nata and Ngoreme, alongside -mara in the same intransitive role. Both, however, seem to allow lability here and also use -mara transitively. A further complication is shown in examples (10a-b), namely that Ngoreme allows a transitive meaning both with and without a causative suffix.

#### (10) Ngoreme

##### a. turénda kumára kuréma

<table><tr><td>tu-ra-ɛ̈nd-a</td><td>ku-mä-a</td><td>ku-rɛ̈m-a</td></tr><tr><td>SM1PL-IPFV-want-FV</td><td>INF-finish-FV</td><td>INF-plough-FV</td></tr></table>

##### b. turénda kumári kuréma

<table><tr><td>tu-ra-ɛ̈nd-a</td><td>ku-mä-i</td><td>ku-rɛ̈m-a</td></tr><tr><td>SM1PL-IPFV-want-FV</td><td>INF-finish-CAUS</td><td>INF-plough-FV</td></tr></table>

‘We want to finish ploughing.’

In Nata, the use of the causative suffix on -mara seems to only coincide with applicative morphology, though the exact nature of these combinations is unclear at this point. Ikoma features yet another state of affairs, whereby -mara ‘end’ and -mari ‘finish’ are used in accordance with a causative strategy. Both -sira and -mara are reflexes of PB roots: *cíd ‘be finished’ and *màd ‘finish (tr.)’, respectively

<footnote n="8">8. ‘die’ is -kwa in Nata, where glide formation and hence the final vowel are allowed in this particular case. ‘kill’ on the other hand is -eta in Ishenyi, with a second-degree vowel. Besides these two morphophonological exceptions, the verbs are formally identical across the varieties.</footnote>

<footnote n="9">9. Note that this verb pair is also suppletive in a number of Ethiopian languages (see Section 4.7 in Treis, this issue)</footnote>

<footnote n="10">10. Despite the non-basic word order, ‘this year’ is an overt object here, indexed by the class 3 object marker on the infinitive verb (which would in turn not be obligatory with a post-verbal object). Fronted objects are not uncommon in WS.</footnote>
(Bastin *et al.* 2002). Apart from potential -mara lability in Nata and Ngoreme, there is one Ishenyi verb pair that looks like a clear-cut case of lability: -γwantīfa 'begin', exemplified both in causal and noncausal use in (11).

(11) Ishenyi

a. γutɔɔka itso umɔɔka nooywantīre

<table><tr><td>γutɔɔka</td><td>itso</td><td>u-m-ɔka</td><td>n-o-V-γwantī-re</td></tr><tr><td>since</td><td>yesterday</td><td>AUP-3-year</td><td>FOC-SM3-PST-begin-PFV</td></tr></table>

‘Starting yesterday, the year began.’

b. tookámara γuywántīfa umɔɔka omúhɛ

<table><tr><td>to-Vká-mar-a</td><td>γu-γwanch-a</td><td>u-m-ɔka</td><td>o-mu-hɛ</td></tr><tr><td>SM1PL-NUCL-finish-FV</td><td>INF-begin-FV</td><td>AUP-3-year</td><td>AUP-3-new</td></tr></table>

‘We have already begun the new year.’

The verb -γwantīfa is most likely borrowed from Swahili -anza 'begin'.<fnref n="11" /> The Swahili verb is a reflex of a stem reconstructable to Proto-East Bantu, namely *yànd 'begin' (Guthrie 1971: 149). The Swahili origin is even more evident in light of the fact that the spirantization of reconstructed /*d/, though a common feature of (East) Bantu languages (see e.g. Schadeberg 1994; Hyman 2019), has not occurred in WS.

Ikoma and Nata have -seema (of unidentified origin) for ‘begin (intr.)’, while Ngoreme has -tanga (PB *táng ‘begin (tr.); go ahead; obstruct the passage’), all following a causative strategy.

### 3. WS COMPARED TO OTHER BANTU LANGUAGES

To relate the WS data presented above to other Bantu languages, we have compiled Table 6 based on Creissels’ (this issue) 13 verb pairs,<fnref n="12" /> with the addition of Kagulu data from Dom *et al.* (2020) and Matengo data from Yoneda (2014; this issue). Ikoma data is included as our representative of the WS group as a whole.

<table><caption>Table 6 — Comparative table of noncausal/causal strategies in Bantu based on Creissels (this issue), Dom *et al.* (2020) and Yoneda (2014; this issue)</caption><thead><tr><th></th><th>A</th><th>C</th><th>E</th><th>L</th><th>S</th><th>Total</th></tr></thead><tbody><tr><td>Ikoma</td><td>3</td><td>8</td><td>2</td><td>0</td><td>0</td><td>13</td></tr><tr><td>Herero</td><td>6</td><td>0.5</td><td>1</td><td>5.5</td><td>0</td><td>13</td></tr><tr><td>Kagulu</td><td>4</td><td>1</td><td>6</td><td>1</td><td>0</td><td>12</td></tr><tr><td>Lingala</td><td>4</td><td>7</td><td>0</td><td>2</td><td>0</td><td>13</td></tr><tr><td>Matengo</td><td>0.5</td><td>0</td><td>9.5</td><td>1</td><td>1</td><td>12</td></tr><tr><td>Swahili</td><td>6</td><td>5</td><td>0</td><td>2</td><td>0</td><td>13</td></tr><tr><td>Tswana</td><td>4</td><td>6</td><td>1</td><td>2</td><td>0</td><td>13</td></tr></tbody></table>

<footnote n="11">11. Swahili /nz/ typically becomes /ntʃ/ in WS, which lacks the voiced sibilant, cf. WS *mwantīfa* ‘Mwanza’, i.e. Tanzania’s second largest city which is geographically close to WS speaking communities.</footnote>

<footnote n="12">12. Creissels (this issue) studies 13 of Haspelmath’s (1993) 31 verb pairs, with some substitutions with similar meanings, restricting himself to “pairs whose noncausal member is a monovalent verb referring to a process (not a state) typically undergone by concrete inanimate entities and easily conceived as occurring without the involvement of a clearly identified external instigator” (Creissels, this issue: Section 1).</footnote>
We can see that the prevalence of causativization in WS, as discussed above, is quite significant from a comparative perspective as well, with Ikoma scoring highest in number of instances of the causative strategy in this small sample. The preference for causativization is actually even more apparent in Table 7, which is based on Haspelmath's 31 verb pairs and where the anticausative to causative (A/C) ratio is taken into account.

<table><caption>Table 7 — Comparative table based on Haspelmath's (1993) verb pairs in Northeast Savannah and Rufiji-Ruvuma (East Bantu)</caption><thead><tr><th></th><th>Guthrie/subgroup</th><th>Verb pairs</th><th>A/C ratio</th></tr></thead><tbody><tr><td>Ngoreme</td><td>JE401/Great Lakes</td><td>26</td><td>0.25</td></tr><tr><td>Kagulu</td><td>G12/North East Coast (&gt; Greater Ruvu)</td><td>32</td><td>1.33</td></tr><tr><td>Matengo</td><td>N13/Rufiji-Ruvuma</td><td>29</td><td>1.25</td></tr><tr><td>Swahili</td><td>G42/North East Coast (&gt; Sabaki)</td><td>31</td><td>1.0</td></tr></tbody></table>

The four languages in Table 7, with Ngoreme representing WS, are Tanzanian Bantu languages in various branches of East Bantu, and thus quite closely related both in terms of geography and genealogy. To our knowledge, Kagulu, Swahili and Matengo are the only other languages from this region, besides the WS languages studied here, with a sound description of the strategies attested for the noncausal/causal alternation. We can see that Ngoreme — along with the other WS varieties — seems to have a considerably lower ratio of anticausative to causative pairs, indicating a stronger preference for causativization across the board. The comparative difference is particularly striking in relation to Swahili, the regionally dominant language with a strong linguistic impact on many East African languages including WS (see Mekacha 1993 for an early account of Swahili influence on Nata). This impact, often referred to as “Swahilization”, has been described as a subtle, gradual and ongoing process of language drift (Brenzinger & Marten 2016; Kutsukake & Yoneda 2019; Bernander forthcoming). Indeed, all our WS consultants are bilingual in Swahili. Yet, except for the Swahili borrowing -ywantša ‘begin (intr./tr.)’ in Ishenyi, Swahili influence does not seem to play any important role in the overall strategies used to code noncausal/causal events in WS.<fnref n="13" />

Some caveats are in order, however. Dom *et al.* (2020) note that Kagulu, where causative derivation through a dedicated suffix is unproductive, still has a lot of lexicalized causatives in pairs counted as equipollent, often coalescing with the derivational suffix of a non-causal stem. This seems to suggest a heavier past reliance on causativization than what is shown in the synchronic analysis. Yoneda (this issue) also points out that Haspelmath’s (1993) analysis of the Swahili data has misinterpretations, as the number of pairs following a causative strategy increases if one accounts for diachronic phonological changes; see, however, Dom *et al.* (this issue) for another view on this.

A brief examination of the wider Mara languages tells us that the unproductivity of the neuter suffix in favour of the reflexive prefix as the most productive coding device for the anticausative strategy is more widely attested than just in WS. Of the South Mara<fnref n="14" /> sibling languages of WS, the neuter is “used rarely” in Zanaki (JE44), and the reflexive is often used instead (Futakamba *et al.* 2013: 6). Ikizu (JE402) seems to have at least some neuter verbs, but Swahili neuters are more typically translated into Ikizu with reflexives or unique lexical verbs, or, interestingly, passives (John B. Walker, p.c.). These circumstances indicate extended functions of the reflexive and passive similar to those found in WS. In the North Mara<fnref n="15" /> branch, Simbiti (JE431) also lacks a productive neuter, and again, the reflexive can be used instead (Walker & Overton 2018: 21). For the wider Kuria group (of which

<footnote n="13">13. We thank Maarten Mous for pointing out this fact to us during our presentation at WOCAL 10.</footnote>

<footnote n="14">14. See Map 1 above where the dotted line separates South Mara from North Mara.</footnote>

<footnote n="15">15. Note that while both South Mara and North Mara seem consistent genetic groupings, their conflation to a unified Mara branch should not be taken for granted (see e.g. Roth & Gibson 2019).</footnote>
Simbiti has been on occasion considered a member), with Kuria (JE43) proper being a neighbouring language to Ngoreme, Cammenga (2004: 251) lists “expressing intransitivity” as a function of the reflexive. On the other hand, he does not mention the productivity of the neuter explicitly, but his examples (2004: 258) include verbs of destruction and the stems ‘read’ > ‘be legible’; the latter might plausibly be a case of borrowing of both the underived and neuter stems from Swahili. The Kuria data available is thus inconclusive, and neither the productivity or unproductivity of its neuter can be ruled out. Further north in Gusii (JE42), a North Mara language spoken in Kenya, the neuter appears to be productive (Cammenga 2002: 378-382).

### 4. WS IN A WIDER TYPOLOGICAL CONTEXT

Trying to relate the WS data to previous cross-linguistically induced claims, we may note that, while the WS language varieties perhaps do not exhibit “an extreme degree of preference for causativization” (Creissels, this issue), their numbers are quite outstanding compared to Creissels’ broader African sample and Haspelmath’s (1993) cross-linguistic sample.

We may further note that WS adheres to the general cross-linguistic tendency that “augmentation” is more straightforwardly marked than “reduction” (Nichols, Peterson & Barnes 2004: 175). In this terminology, augmentation is the addition of formal marking to the valency increasing operation — in this case the causal event — while reduction is the overt marking of the valency-decreasing process, i.e. the marking of the noncausal event (Nichols et al. 2004; see also the Introduction, this issue, for further details on the varying correspondence type labels that occur in the literature). Furthermore, the coding of the noncausal event typically consists of different strategies that are also associated with greater polyfunctionality. In the case of WS, this would of course be the use of, for example, reflexives and passives. On the other hand, the WS data seem to counter Nichols et al.’s proposal that causativization-prominence in languages goes hand in hand with a lack of a passive or “other [transitive subject]-removing/demoting processes” (a counterexample that is also pointed out by Creissels, this issue, with regard to Bantu and other African languages). Despite its heavy reliance on causativization, WS does have a passive and, despite its extended functions discussed above, it is perfectly productive as a bona fide passive, as shown in (12), topped with adjunct agent phrases. In (12a), the passive form of the perfective suffix -irɛ is -iru due to the causative -i in -βooki ‘wake up (tr.)’. In (12b), on the other hand, the underived stem -ruma ‘bite’ takes the perfective passive suffix -uru.<fnref n="16" />

#### (12) Ishenyi

a. neeβóókiru naaβáána
ne-V-βook-iru
FOC:SM1SG-PST-wake_up-CAUS.PFV.PASS
na=a-βa-Vna
COM=AUP-2-child
‘I was woken up by the children.’

b. jiniſáŋga naromuru naſſintʃóki
jiniſanga
1a.paternal_aunt
n-a-rom-uru
FOC-SM1-sting-PFV.PASS
na=ʃi-n-ʃoki
COM=10-bee
‘Her/his aunt was stung by bees.’

As we have discussed above, WS features low productivity of some of the derivational suffixes most associated with anticausative functions in Bantu, namely, the neuter and the intransitive separative (cf. Dom et al. 2018). It should perhaps be noted that the latter involves semantics largely coinciding with that of the neuter, suggesting a common origin in the distant past (Schadeberg & Bostoen 2019: 186). In any case, this unproductivity and, on the flipside, the more innovative anticausative strategies may well be worth further exploration from a comparative perspective.

<footnote n="16">16. In Ishenyi, the passive causes the same root vowel shift /u > o/ (phonetically ʊ) as described in Section 2.2.1 for the causative suffix -i.</footnote>
## 5. CONCLUSIONS

In conclusion, this paper has given an account of the expression of noncausal/causal verb pairs in Western Serengeti language varieties based on a list of 31 verb pairs provided by Haspelmath (1993). We have shown that in WS, the most common strategy by far for distinguishing causal verbs from noncausal verbs is the causative strategy, with derivation via the causative suffix. Apart from this main strategy, the causative suffix is predominantly used in equipollent pairs to derive the causal members.

The anticausative and equipollent strategies are less common, and they are formally a lot more diverse, with several kinds of derivational affixes used, namely reflexives, neuters, separatives and passives. The reflexive appears, however, to be the dominant middle voice marker in WS more widely, and it is therefore unsurprising that it should also in this sample be the main marker on noncausal verbs involving the anticausative strategy. This fact seems likely to be connected to the comparatively low productivity in these language varieties of the neuter and intransitive separative, both of which might be expected to feature prominently in anticausativization in a typical East Bantu language.

In addition to presenting and discussing the WS data in some detail and establishing the aforementioned state of affairs in noncausal/causal alternations, we have shown that WS rather stands out in comparison to other East Bantu languages, even other Tanzanian languages specifically, in its preference for the causative strategy. This moreover demonstrates that significant variation can be found in the formation on noncausal/causal events even between closely related languages that can, in many other ways, be considered largely similar.

## ACKNOWLEDGMENTS

This work is part of the Mara project, carried out at the University of Helsinki and funded by the Kone Foundation (https://blogs.helsinki.fi/mara-project/). The project aims to compile (comparative) grammars of the Western Serengeti languages. We would also like to thank the reviewers, the guest editors — Sebastian Dom in particular — and the editor, Yvonne Treis, as well as our audience at the 10th World Congress of African Linguistics. Finally, we are grateful to the Western Serengeti speakers who have worked with us.

## ABBREVIATIONS

<table><tr><td>APPL</td><td>applicative</td></tr><tr><td>ASS</td><td>associative</td></tr><tr><td>AUP</td><td>augment prefix</td></tr><tr><td>CAUS</td><td>causative</td></tr><tr><td>COM</td><td>comitative</td></tr><tr><td>DEM</td><td>demonstrative</td></tr><tr><td>FOC</td><td>focus</td></tr><tr><td>FV</td><td>final vowel</td></tr><tr><td>INF</td><td>infinitive</td></tr><tr><td>IPFV</td><td>imperfective</td></tr><tr><td>intr.</td><td>intransitive</td></tr><tr><td>NEUT</td><td>neuter</td></tr><tr><td>NUCL</td><td>nucleative</td></tr><tr><td>OM</td><td>object marker</td></tr><tr><td>PASS</td><td>passive</td></tr><tr><td>PERS</td><td>persistive</td></tr><tr><td>PFV</td><td>perfective</td></tr></table>
<table><tr><td>PL</td><td>plural</td></tr><tr><td>PROG</td><td>progressive</td></tr><tr><td>PROX</td><td>proximal</td></tr><tr><td>PST</td><td>past tense</td></tr><tr><td>REFL</td><td>reflexive</td></tr><tr><td>REL</td><td>relative</td></tr><tr><td>SEP</td><td>separative</td></tr><tr><td>SG</td><td>singular</td></tr><tr><td>SM</td><td>subject marker</td></tr><tr><td>tr.</td><td>transitive</td></tr><tr><td>WS</td><td>Western Serengeti</td></tr></table>

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<table><caption>APPENDIX: LIST OF WS VERB PAIRS COUNTED BASED ON HASPELMATH (1993) AND YONEDA (2014)</caption><thead><tr><th></th><th>Ikoma</th><th>Ishenyi</th><th>Nata</th><th>Ngoreme</th></tr></thead><tbody><tr><td>1 boil</td><td>-hiif-ok-al/-hiif-i (E)</td><td>-hiis-ok-al/-hiis-ok-i (C)</td><td>-hiis-ok-al/-hiis-i (E)</td><td>-hiis-ɔk-al/-hiis-ɔk-i (C)</td></tr><tr><td>2 freeze</td><td>-rural/-rur-i (C)</td><td>-rural/-rut-i (C)</td><td>-rural/-rur-i (C)</td><td>-rural/-rut-i (C)</td></tr><tr><td>3 dry</td><td>-omal/-om-i (C)</td><td>-hoomal/-hoom-i (C)</td><td>-omal/-om-i (C)</td><td>-hɔɔmal/-hɔɔm-i (C)</td></tr><tr><td>4 wake up</td><td>-βookal/-βook-i (C)</td><td>-βuukal/-βooki (C)</td><td>-βookal/-βooki (C)</td><td>-βɔɔkal/-βɔɔki (C)</td></tr><tr><td>5 go out/put out</td><td>-rimal/-rim-i (C)</td><td>(n.a.)</td><td>-rimal/-rim-i (C)</td><td>-rimal/-rim-i (C)</td></tr><tr><td>6 sink</td><td>-mer-ul/-mer-i (E)</td><td>-i-meril/-meri (A)</td><td>-mer-ul/-mer-i (E)</td><td>(n.a.)</td></tr><tr><td>7 learn/teach</td><td>-eyal/-ey-i (C)</td><td>-eyal/-ey-i (C)</td><td>-eyal/-ey-i (C)</td><td>-eyal/-ey-i (C)</td></tr><tr><td>8 melt</td><td>-jajal/-jaj-i (C)</td><td>-jajal/-jaj-i (C)</td><td>-jajal/-jaj-i (C)</td><td>-jarayana/-jarayan-i (C)</td></tr><tr><td>9 stop</td><td>-imereral/-imerer-i (C)</td><td>-imeeral/-imerer-i (C)</td><td>-emeereral/-emeerer-i (C)</td><td>-imeɛɛral/-imeer-i (C)</td></tr><tr><td>10 turn</td><td>-inaara/-inaar-i (C)</td><td>-iroyooral/-iroyoor-i (C)</td><td>-inaara/-inaar-i (C)</td><td>-inaara/-inaar-i (C)</td></tr><tr><td>12 burn</td><td>-akal/-ak-i (C)</td><td>-okal/-ok-i (C)</td><td>-okal/-ok-i (C)</td><td>-okal/-ok-i (C)</td></tr><tr><td>13 destroy</td><td>-sar-ek-al/-sar-i (E)</td><td>-sar-ik-al/-sar-i (E)</td><td>-sar-ek-al/-sar-i (E)</td><td>-sar-ek-al/-sar-i (E)</td></tr><tr><td>14 fill</td><td>-iforal/-ifor-i (C)</td><td>-ifural/-ifor-i (C)</td><td>-iforal/-ifor-i (C)</td><td>-ifɔɔr-al/-ifɔɔr-i (C)</td></tr><tr><td>16 begin</td><td>-seeɛnal/-seem-i (C)</td><td>-antfal/-antf(a) (L)</td><td>-seeɛnal/-seeɛn-ɛr-i (C)</td><td>-tangal/-tang-i (C)</td></tr><tr><td>17 spread</td><td>-sanfal/-sanf-i (C)</td><td>-sanfal/-sanf-i (C)</td><td>-muntanal/-muntan-i (C)</td><td>-mankanal/-mankikan-i (C)</td></tr><tr><td>18 roll</td><td>-hiringital/-hiringit-i (C)</td><td>-hiringital/-hiringit-i (C)</td><td>-hiringital/-hiringit-i (C)</td><td>-hiringital/-hiringit-i (C)</td></tr><tr><td>19 develop ('grow')</td><td>-koral/-kor-i (C)</td><td>-koral/-kor-i (C)</td><td>-koral-kor-i (C)</td><td>-kiinal-kiin-i (C)</td></tr><tr><td>19 develop ('continue')</td><td>-endereral/-enderer-i (C)</td><td>-enderal/-ender-i (C)</td><td>-enderal/-enderer-i (C)</td><td>-yɛnderi/-yɛnder-i (C)</td></tr><tr><td>20 get lost/lose</td><td>-βora/-βor-i (C)</td><td>-βora/-βor-i (C)</td><td>-βora/-βor-i (C)</td><td>-sira/-taβuta (S)</td></tr><tr><td>23 rock</td><td>-itundal/-itund-i (C)</td><td>-itundal/-itund-i (C)</td><td>-itundal/-itund-i (C)</td><td>-i-hintʃi/-hintʃi (A)</td></tr><tr><td>24 connect</td><td>-rɔɔβal/-rɔɔβ-i (C)</td><td>-rɔɔβal/-rɔɔβ-an-i (C)</td><td>-rɔɔβal/-rɔɔβ-ir-a (C)</td><td>-rɔɔβal/-rɔɔβ-an-i (C)</td></tr><tr><td>25 change</td><td>-i-γarural/-γarura (A)</td><td>-i-γaaroni/-γarura (A)</td><td>-i-γarural/-γarura (A)</td><td>-i-honfɔɔra/-hɔɔnfɔɔra (A)</td></tr><tr><td>26 gather</td><td>-i-kom-an-al/-koma (A)</td><td>-i-kuma/-kuma (A)</td><td>-i-kom-an-al/-koma (A)</td><td>-i-kɔm-an-al/-kɔm-an-i (E)</td></tr><tr><td>27 open</td><td>-iy-ok-al/-iy-or-a (E)</td><td>-hung-uk-al/-hung-ur-a (E)</td><td>-iy-ok-al/-iy-or-a (E)</td><td>-iy-ɔk-al/-iy-ɔr-a (E)</td></tr><tr><td>28 break</td><td>-βun-ek-al/-βuna (A)</td><td>-βon-ik-al/-βuna (A)</td><td>-βun-ek-al/-βuna (A)</td><td>-ten-ek-al/-tena (A)</td></tr><tr><td>29 close</td><td>-i-jiγaral/-iyara (A)</td><td>-i-hunga/-hunga (A)</td><td>-iyar-ɛr-ul/-iyara (A)</td><td>-i-jiγaral/-iyara (A)</td></tr><tr><td>30 split</td><td>-at-ɛk-al/-at-i (E)</td><td>-βaar-uk-al/-βaar-ur-a (E)</td><td>-at-ɛk-al/-at-i (E)</td><td>-at-ɛk-al/-at-i (E)</td></tr><tr><td>31 die/kill</td><td>-kul-ita (S)</td><td>-kul/-eta (S)</td><td>-kwal-ita (S)</td><td>-kul-ita (S)</td></tr></tbody></table>
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