Source: https://www.afrikanistik-aegyptologie-online.de/archiv/2016/4523/
Timestamp: 2019-04-24 21:55:10+00:00

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In this paper, two verbal configurations in Nyakyusa, a Bantu language of southern Tanzania (Guthrie-Code M31), are discussed with regard their synchronic meaning and use and their diachronic origins. The first configuration constitutes a dedicated narrative paradigm whose shape lɪnkʊ-...-fv resembles a present progressive or simple present widespread across Bantu (Bastin 1989a, 1989b). Based on Haspelmath (1998), it is argued that the specialization of this construction to narrative discourse is a side-effect of the advanced grammaticalization of a new present tense construction marked by a prefix (i)kʊ-…-fv. The second configuration in question features the prefix of this new present plus a general imperfective suffix -aga, yielding a non-compositional future-oriented modal meaning. Drawing on data from languages of the wider area and on findings from formal semantics (e.g. Krifka et al. 1995), it is argued that the present-day function of this second construction goes back to the restriction of the ambiguous simple present to a habitual/generic reading plus the semanticization of a future-oriented implicature.
In diesem Artikel werden zwei Verbkonfigurationen im Nyakyusa, einer Bantu-Sprache des südwestlichen Tansanias, hinsichtlich ihrer synchronen Bedeutung und Gebrauch sowie hinsichtlich ihrer Diachronie besprochen. Bei der ersten Konfiguration handelt es sich um ein dezidiert narratives Paradigma, welches hinsichtlich seiner Komposition lɪnkʊ-...-fv einer im Bantu weit verbreiteten präsentischen Verlaufsform oder eines allgemeinen Präsens gleicht (Bastin 1989a, 1989b). Auf Grundlage von Haspelmath (1998) wird dafür argumentiert dass die Spezialisierung dieser ein Nebeneffekt dessen ist, dass ein neues Präsens (i)kʊ-…-fv in seiner Grammatikalisierung fortschreitet. Die zweite besprochene Konfiguration besteht aus dem Präfix jenes neuen Präsens plus einem Imperfektiv-Suffix -aga. Zusammen ergeben diese eine nicht-kompositionale zukunftsorientierte modale Bedeutung. Mit Rückgriff auf Daten benachbarter Sprachen und Erkenntnissen aus der formalen Semantik (z.B. Krifka u.a. 1995), wird dafür argumentiert, dass die synchrone Funktion dieser Konfiguration auf die Restriktion des mehrdeutigen Präsens auf eine habituelle/generische Lesart zurückgeht, zusammen mit der Semantisierung einer zukunftsorientierten Implikatur.
The aim of this study is to trace the diachronic developments that have driven two formally present tense (or non-past) verbal paradigms in Nyakyusa, a Bantu language of Tanzania (Guthrie-Code M31 according to Maho 2009), to develop into a narrative marker with past reference and a modal future respectively.  It will be argued that these two developments are linked to each other, in that they are both side effects of the grammaticalization of a new simple present. To demonstrate this, an internal reconstruction as well as a comparative Bantu perspective will be presented.
In this section, I will first give some basic information about Nyakyusa (§1.1) to then explore Haspelmath's (1998) seminal discussion of old presents (§1.2).
Nyakyusa is a Bantu language spoken in the Mbeya region of south-western Tanzania, on the coastal plains of Lake Nyassa (Lake Malawi) and in the hills to the north of it (e.g. Wilson 1963:1). Estimations of the number of speakers vary between 732,990 (Muzale & Rugemalira 2008) and 805.000 (Lewis 2009). Nyakyusa is surrounded entirely by other Bantu languages, among them Kinga (G65), Wanji (G66), Kisi (G67) and Safwa (M25). Its closes relatives are Ndali (M301), bordering to the west, and Ngonde (also M31) to the south (e.g. Nurse & Phillipson 2003).
There is no official orthography for Nyakyusa. Therefore, a practical orthography will be used throughout this study. The basic rules are as follows: <aa, ee, ɪɪ, ...> designate long vowels; vowels before NC-clusters are predictably long and therefore length is not marked; <ng'> = /ŋ/, <ny> = /ɲ/, <nia, nie, ...> = /nʲa, nʲe, …/, <y> = /j/, <j> = /ɟ/; <n, m> preceding a voiceless plosive, another nasal or a fricative designate a syllabic nasal; preceding a voiced plosive, syllabic nasals are rendered <n̩, m̩>; <b, g> represent the approximants [β, ɣ], except following a nasal. Lastly, Nyakyusa does not feature distinctive tone and has regular penultimate stress accent.
The finite verb in Nyakyusa has the typical agglutinative structure of a Narrow Bantu language (e.g. Nurse 2008:21), which can be understood as having a number of slots for derivational and inflectional affixes that frame the verbal root. Throughout this study, Güldemann's (1999) segmentation and labels for the individual slots are followed. Figure 1 illustrates this linear structure. Inflection for tense, mood and aspect (TMA) in Nyakyusa is found mainly in the post-initial and final slots.
The data for this study was collected during three field trips between 2013 and 2015. Additional data comes from elicitation with two language assistants living in Germany. A number of additional texts, mostly written, have kindly been made available by the Mbeya office of SIL International and by Knut Felberg.
Haspelmath (1998) discusses a number of anomalies of verbal paradigms across such genetically and typologically diverse languages as Welsh (Celtic, Indo-European), Udmurt (Finno-Ugrian), Kannada (Dravidian) and Turkish (Turkic). These anomalies include a less formal marking of the future vs. the present tense or the indicative vs. the subjunctive mood, 'irregular' verbs that in their future-tense form denote present tense, and also cases of curious polysemies, in which a single verbal paradigms expresses the semantically unrelated temporal-aspectual meanings of habitual/generic  in some contexts and future time reference in others. In the latter case, these paradigms are also commonly used in other functions, such as in proverbs or – of special relevance for this study – in narrative discourse.
Haspelmath argues that in all these cases we are dealing with old simple present tense constructions. As he points out, these developments do not by themselves constitute cases of grammaticalization, as we are not dealing with lexical items turning into grammatical ones. Rather, we are dealing with already grammaticalized constructions undergoing a change in meaning and use as the side effect of another grammaticalization process. When a former progressive construction advances in grammaticalization and acquires a wider meaning (see Bybee et al 1994), the old construction may persist in some of its specialized uses and continue to be used with certain frequent lexemes, viz. the cases of 'irregular verbs'.
A prime example of such a development is found in modern Turkish. In this language we find a renewed present tense (or general imperfective) construction (1), that goes back to a periphrasis consisting of a converb of simultaneity plus an auxiliary (2). As the glosses in (1) indicate, in the present-day language this construction can express both a progressive as well as a habitual/generic meaning.
The old Turkish present, commonly called aorist in the Turkologist tradition, can be reconstructed for Proto-Turkic. As the older Ottoman Turkish examples (3a, b) show, in earlier stages of Turkish, the aorist could give a progressive reading, among others. In modern Turkish, however, it has the meaning of disposition or habituality (4a), probable future (4b), and is also used in narratives, especially in traditional styles (4c). Note that the surface realization of the aorist suffix and following agreement markers is subject to vowel harmony.
In the following, I will discuss two intriguing variations on the theme observed by Haspelmath. The first one concerns a former simple present that has become a narrative marker with past time reference (section 2). The second case consists of the constructionalization of the new simple present plus imperfective suffix as a modal future (section 3).
A salient feature of relating past narratives in Nyakyusa is the frequent employment of verbal forms of the shape illustrated in (5), which often appear in long chains. While comparable devices, often labelled narrative, narrative tense, consecutive or subsecutive are common in African languages (Dahl 1985:113f), including Bantu (Nurse 2008:120), the formal composition of what will henceforth be called the narrative tense  is conspicuous: it can be segmented into a copula together with an infinitive complement additionally marked for locative class 18 (5). The copula lɪ, unlike regular verbs in Nyakyusa, forms it present tense without any overt prefix (6). Although formally speaking the narrative tense is thus a present tense construction, it always has a past reading. For the purpose of illustrating formal aspects of the narrative tense, we limit the discussion here to elicited single sentences and turn to contextual examples in §2.2.
While the composition of the narrative tense is still transparent, the fact that no material can intervene between the copula and its complement is indicative of an advanced stage of grammaticalization and shows that from a synchronic point of view this construction should be analyzed as consisting of a prefix lɪnkʊ- in the post-initial slot, plus the default final vowel (9). Further indications that the lɪ-portion no longer functions as a copula comes from the fact that the construction is compatible with the copula verb ja 'be, become', as in (11) below.
In the following sections, the employment and semantics of the Nyakyussa narrative tense will be summarized (§ 2.1), and the diachronic development of this construction then traced (§ 2.3).
The time of the situation is first established, either explicitly in the first verb in a string, or implicitly […] All following verbs in the sequence are then marked by a special narrative marker, which replaces the tense marker appropriate to the time established by the first verb. Just because most sequences deal with past events, this special marker is most frequent in past narratives, less frequent in timeless events, followed by futures. It also occurs across sentences and utterances, in which case the context most often crosses sentence boundaries and characterizes a long utterance. Use of the special marker can be suspended and then deliberately reintroduced by the speaker to stress continuity.
As Nurse's description leaves open various dimensions of variation, it is worth taking a closer look at the Nyakyusa narrative tense in terms of patterns of usage and semantics in the narrow sense. This will ultimately also shed light on the diachronic development of this construction.
Within the macro-structure of narrative discourse, the narrative tense is essentially confined to storyline events, i.e. Labov & Waletzky's (1967) complication, evaluation and resolution sections. The only exceptions are endings of the type illustrated in (11).
The narrative tense is not used with material ancillary to the storyline or flashbacks. But note that this association with the storyline is a one-way conditional:unlike what has been reported for other African languages such as Supyire (Senufo), where a narrative marker is used “in all but the initial main line clause” (Carlson 1994:34), in Nyakyusa, storyline events are also, in varying degrees, depicted with the use of the past perfective. As argued for by Persohn (2016), this forms part of a larger pattern, in which narrative discourse is construed around the notion of thematic continuity (Givón 1984).
Concerning the aspectual semantics of the narrative tense, an examination of the text corpus shows that it is restricted to episodic sentences, that is “those whose main predicate has a situation argument bound by existential closure; they report a specific event or occasion” (Krifka et al. 1995:36). This includes reports of specific occasions featuring plural events (see Carlson 2009), such as (13). By definition this excludes habitual/generic statements. As for the present tense in the subordinate clause of (13), see <19> above on temporal clauses in Nyakyusa.
Context: Children have killed a snake that was lying in front of them on the path. Now they try to pass the snake’s dead body.
Apart from its restriction to episodic sentences, the narrative tense can be considered unspecified for aspect. With inchoative verbs and other types of verbs that feature a change-of-state or inherent endpoint as part of their lexical meaning, the narrative tense typically refers to the latter. This is illustrated in (14) with the inchoative verb ɪma 'stand, stop'.
With activity-type verbs the reading is context-sensitive. To begin with, the narrative tense can give a reading of an eventuality as a discrete whole. This is most obvious in those cases where the discursive environment clearly delimits the occurrence, as in (15b). The use of the narrative tense with the copula verb ja 'be(come)' plus associative and infinitive in (15c) is a common device in Nyakyusa narratives, which denotes the beginning a new occupation or dedication of the subject.
A progressive reading is also possible. In the extract given in (16), Tugutu (a type of bird) tricks Hare in a race. He remains at the start (16d), while Hare runs (16b, e). The act of running is construed as an ongoing activity contemporaneous with the acts of speaking (16c) and completing the first mile (16f).
Closely linked to the question of aspectual semantics is that of sequential ordering. An often-repeated assumption in the literature has it that sequential ordering is part and parcel of the semantics of narrative markers. Thus, Nurse (2008:121) generalizes from a Swahili example that “the narrative explicitly sequences events […] and says that […] the second situation is later than the first”. A closer examination of Swahili narratives, however, brings up a number of counterexamples (Contini Morava 1987:112f). Concerning other Bantu languages, Morrison (2011:277) notes for Bena G63 that the “[narrative tense] is often best translated as ‘and then X’” (emphasis added), while Seidel (2015) makes a similar observation for Yeyi R41. However, as example (16) above already indicates, sequential ordering is not a semantic component of the Nyakyusa narrative tense. (17) is an additional example. While (17a, b) describe eventualities that happen in sequence, (17c– e) describe various details of one and the same eventuality and could be freely swapped with each other without changing the underlying sequence of events.
The question now arises as to how a verbal periphrasis of the shape copula + locative + infinitive became the Nyakyusa narrative tense with the characteristics just described.
If we look at the central TMA categories of the present-day language, we find a simple (or imperfective) present, marked through a prefix (i)kʊ- in post-initial position and the default final vowel -a. The prefix often induces a change in the vowel quality of the preceding subject marker, the exact characteristics of which are subject to topolectal variation (see Persohn 2016:ch. 3). The kʊ- portion is identical to the noun class 15 (infinitive) prefix, which is clearly an indication that the source of the present-day simple present has been a verbal periphrasis, which in all likelihood has followed the familiar grammaticalization path (location) > progressive > imperfective or simple present (Bybee et al. 1994). Persohn & Bernander (forthcoming) show that the changes in the vowel of the preceding subject marker, often to /i/ is an areal feature of southwestern Tanzania and, by applying a comparative perspective, argue that the auxiliary of the former periphrasis is a reflex of Proto-Bantu *jiÃkad ‘dwell; be; sit; stay’ (Bastin et al. 2003).
Now recall from §1.2 that Haspelmath (1998) shows how the advancing grammaticalization of a former progressive to a fully fletched simple present can lead to an older construction becoming restricted to specialized uses, a typologically common one of which is its use as a narrative marker. As was remarked in §2.1, verbal periphrases that are identical in composition to the Nyakyusa narrative tense are widespread all across the Bantu speaking area, either as present progressives or, more advanced in grammaticalization, as simple presents. This wide geographic distribution suggests an old shared innovation. A simple present marked by kʊ- together with the specific changes in the vowel quality of a preceding subject marker (§2.3), however, can be shown to be a more recent and independent development restricted to the languages of southwestern Tanzania (Persohn & Bernander, forthcoming). All this suggests that in the case of Nyakyusa the extension of a former periphrastic progressive to the 'new' simple present has confined an old present (now the narrative tense) to its usage in narrative discourse. As one anonymous reviewer points out, this does not explain why the old present (now the narrative tense) retains more segmental material than the more recently grammaticalized one. We may speculate that its indexical function of signaling narrative discourse has 'rescued' the narrative tense from further erosion.
The distribution of the narrative tense in the present-day language supports the scenario outlined above. As described in §2.2, the narrative tense is essentially confined to storyline eventualities. This is exactly what would be expected from a present tense employed as a narrative present (Fludernik 1991:368). The lack of coding of event sequentiality is another case in point: it would be hard to see how a former imperfective present came to include sequential semantics. Note that – unlike the cases described by Haspelmath (1998) – the Nyakyusa narrative tense is used not only in folk narratives, but in all styles of narrative discourse, including e.g. personal narratives and Bible translations. It is likely that its restriction to narrative discourse, which normally takes places in the past tense, has consequently led the narrative tense to take over past time reference as part of its semantics, while its frequent use and confinement to narrative discourse has led to bleaching of its aspectual value. A development along these lines is also reported for Biblical Hebrew. Robar (2014) illustrates at length how in this language the so-called wayyiqtol construction constitutes a former simple present, whose extensive use as a narrative present with the pragmatic function of signalling continuity has led to a bleaching of its original semantic content. In the case of Hebrew, this has even gone one step further, allowing for the wayyiqtol construction to take over any tense, aspect or modal value from its antecessor. A possible explanation for this type of bleaching is found in Fleischmann (1990:52–63). Fleischmann argues that a narrative present can receive what she calls a ‘plus-interpretation’, that is, the simple present as the least specific form takes over the meaning adequate to context. We may assume that the specialization of the old Nyakyusa present (now the narrative tense) in narrative discourse has favoured the semanticization of this erstwhile contextually evoked meaning. Note at this point that in many other Bantu languages, e.g. Totela (K41; Crane 2011), infinitives are used as narrative markers. A cross-Bantu tendency to use semantically underspecified forms in narrative discourse may thus have had further influence in the semantic shift of Nyakyusa's narrative tense.
To summarize, the Nyakyusa narrative tense, marked with a prefix lɪnkʊ- goes back to a verbal paraphrase that is widespread in Bantu as a present progressive or a simple present. In Nyakyusa, however, this configuration is restricted to storyline eventualities in narrative discourse and always refers to the past. Further, it is unspecified for aspect. The existence of a simple present with clear traces of a verbal paraphrase in the present-day language suggests a displacement of an old present as a side effect of the advancing grammaticalization of a new one, along the lines of Haspelmath (1998). The adoption of past time reference and the loss of aspectual specification can then be understood as later developments.
The second case to be discussed in this study concerns a verbal configuration whose meaning cannot be derived from its constituent parts. This construction, which will be named modal future, is formed with the simple present prefix kʊ- in the postinitial slot. The final slot is filled with the imperfective suffix -aga. Unlike what would be expected from its composition, this verbal configuration does not have a present progressive or habitual/generic reading, but instead expresses a future-oriented type of modality (19). A closer examination of its semantics will be given in <32>.
It is worthwhile at this point to have a closer look at both constituent morphemes of the modal future, the simple present prefix kʊ-, as well as the imperfective suffix -aga. As the following example shows, the simple present by itself has a progressive reading, a habitual/generic one, as well as one of a near or probable future (20). The futurate reading deserves a short discussion. It is not uncommon for the languages of the world to extend a simple present or general imperfective to include future time reference; see Bybee et al 1994, among others. This situation is also found, both synchronically and diachronically, in many Bantu languages (Nurse 2008:118f, 297f). In recent discussions of aspectuality and temporality in Bantu the futurate reading is commonly linked to the progressive one, in that both are understood as a function of the construal of an eventuality as incomplete at utterance time (e.g. Kershner 2002:102f; Osa-Goméz 2014:150f). It is important to note that this futurate use of the simple present in Nyakyusa shows a different distribution from the modal future and does not have the same modal flavour.
As for the imperfective suffix -aga (-ege in the subjunctive mode), this morpheme likewise gives a progressive as well as a habitual/generic reading. (21) illustrates this for the past imperfective, (22) for the subjunctive mood.
It has been shown in the preceding paragraphs that the Nyakyusa modal future is formed by a combination of a simple present prefix and a general imperfective suffix. While a future-oriented reading as such could be explained as an extension of the progressive reading, this does not explain the seemingly redundant twofold imperfective marking. Also, it does not predict the construction's distribution nor its specific meaning.
The semantics of the modal future can be summarized as depicting a state-of-affairs-to-be as a settled fact. That is, it expresses various kinds of modal necessity (e.g. metaphysical, circumstantial, teleological) together with relative future time reference. The following exposition of its most common uses will illustrate this meaning. For a discussion of the absolute, not specifically modal, future in Nyakyusa see <39> below.
To begin with, the modal future is used in habitual/generic expository contexts, where it indicates the next step (23d) in a sequence of eventualities, and, closely related, the consequences of specific behaviour (23a, f, g). Note that we are dealing with states-of-affairs that stand in a temporal relationship relative to each other and which are not set in an absolute future time.
Another example from an expository text is given in (24). Again, the construction in question indicates the next step in a sequence of eventualities (24b, e, f). We will see below that this type of usage within a generic context plays an important role in the reconstruction of the diachronic development of the modal future.
The modal future construction is also very frequent in commissive speech acts. As the name indicates, these are utterances which “commit the speaker to a certain cause of events” (Austin 1962:156). Proto-typical cases include promises (25), assurances (26) and announcements (27).
Context: A girl has eloped with a man. Her father has tracked them down.
n- gw -i-pʊʊl- aga .
Context: Hare and Spider want to climb up a tree. Hare has told Spider that he does not know how to.
Context: Elephant, in his function as the oldest of animals, has called a meeting.
The modal future is also found with a certain directive force. This is especially common when describing the target procedure of a plan involving the hearer, as in (28).
Context: Hare begs local people to help him descend from a tree, where he is trapped.
Interestingly, all tokens of the modal future within questions in the text corpus constitute rhetorical questions. An example is given in (29). Here the narrator employs a narrative ruse by letting the trapped protagonist ask himself if his death in a pit is his inevitable fate (29a), only to let him answer to the contrary (29b) and allow actions to follow (29c).
Context: Hare is in a pit and afraid to leave.
In elicitation, the modal future was also accepted in prompts for a promise, as in (30), the interrogative counterpart to (25) above.
Context: The hearer owes you money.
Context: What happens if I eat this mushroom?
The future proclitic is not limited to the simple present, but can be freely used with any verbal configuration that has future orientation per se or that can be used in such a way, including the modal future. Thus in (32) the proclitic is used in Tortoise's promise in order to set the time of taking the money in a future situation (the ‘not now’, so to speak).
Context: Tortoise is making an excuse to not immediately pay back his debts.
As has been seen in the previous section, the meaning and use of the Nyakyusa modal future at first glance seems at odds with its formal composition. A look at some of Nyakyusa's neighbouring languages, however, gives a first indication of what has probably been the starting point for the development of its present-day functions.
In the Tanzanian variety of Nyakyusa's western neighbour Ndali (M301), we find a simple present construction, formed with a prefix ku- and the default final vowel -a. Unlike the Nyakyusa simple present (see § 2.2), the Ndali construction does not induce any change in the vowel quality of the subject prefix. As we have seen above for Nyakyusa, the Ndali simple present has both a progressive and a habitual/generic reading. The addition of the imperfective suffix -aga, however, restricts the meaning of the construction to a habitual/generic one (Swilla 1998). The very same situation is found in Nyakyusa's southeastern neighbour Kisi (G67; Gray, m.s.) and in Malila (M24), another Bantu language of the wider area (Helen Eaton, p.c.).
It has been observed repeatedly in the literature that there is a strong notional link between habitual/generic aspect on the one hand, and modality on the other. Thus Givón (1994) considers habitual/generic a modal category. Likewise Ziegeler (2006:21) notes that habitual/generic aspect is a “prime candidate for […] categories residing on the aspect-modality interface”. Others, such as Hacquard (2006), consider imperfectivity as such inseparable from modality. Of special interest for the subject at hand, Brinton (1988:140f) observes that habituals/generics intersect with future-oriented epistemic modality in that “a present habit is presumed to continue into the future”.
These observations may be made more operable by resorting to the tenets of formal semantics. Habitual/generic statements are normally understood as law-like or “’principled generalizations’ […] not […] more ’accidental’ facts” (Krifka et al. 1995:44). A theoretical puzzle for formal accounts of semantics lies in the fact that these generalizations allow for exceptions. Thus a statement like ’dogs have four legs’' is generally considered true, even though specific dogs may have fewer legs, e.g. due to an accident (see Leslie & Lerner forthcoming for an overview). The standard solution to this paradox lies in assuming normalcy conditions: habitual/generic statements are understood as assertions about the most normal cases. Stated in terms of possible worlds semantics (e.g. Kratzer 1977,1981), in the subset of accessible theoretically possible worlds that rank as closest to the ideal of normality, the proposition contained in the habitual/generic statement is true for each entity of the class.
Two points about such an understanding of habitual/generics are of central importance for this study. First, the universal quantification over the most normal possible worlds equals modal necessity. Second, the subset of the most normal possible worlds includes the most normal future versions of the actual world. In the absence of information to the contrary, this is accompanied by a generalized implicature (see Grice 1981; Levinson 2000) that any future version of the actual world falls within this subset of normal worlds. Thus, when one states (33a), by default this is understood to imply (33b).
On Saturday mornings I go swimming.
As has been seen initially, the semantics of the Nyakyusa verbal configuration kʊ-...-aga can be described as one of modal necessity plus relative future time. Now, let us assume that in an earlier chronolect of Nyakyusa, the situation concerning this verbal configuration paralleled the one found currently in Tanzanian Ndali, Kisi and Malila i.e. the suffix -aga restricting the simple present to a habitual/generic reading. Under this assumption the present-day semantics of the modal future can be understood as a motivated extension of this earlier meaning. As the preceding discussion has shown, habituals/generics can be understood as expressions of modal necessity in the most normal possible worlds. Understood in this way, the modal force (necessity) of the construction in question constitutes a direct continuation of the earlier situation, while the indication of a future state-of-affairs already featured as a generalized implicature. The leap from habitual/generic to modal future thus consists in the semanticization of this implicature.
It seems reasonable to assume that, in an earlier stage of Nyakyusa, the very restriction of the ambiguous simple present to a law-like reading led to a strengthening of the future-oriented implicature. This would have ultimately favoured the semantic split-off of this verbal configuration. Note that at the systemic level the configuration in question would have been redundant, as its basic meaning could already be expressed by the bare simple present. In this scenario, the employment of the construction with subsequent steps and consequences in expositions, e.g. (23, 24) above, constitutes an older type of use. Being still consistent with the diachronic habitual/generic semantics of the construction, this use may well have constituted a ‘bridging context’ (e.g. Evans & Wilkins 2000; Heine 2002) for the new meaning to become conventionalized. Once the verbal configuration in question acquired the meaning of something that will necessarily happen at a subsequent time, other uses, e.g. in commissive speech acts, offered themselves.
Further support for this scenario may be found in Nyakyusa's eastern neighbour Kinga (G65). In this language we find a simple present formed with a prefix i(kʊ)-.  In the variety described by Wolff (1905), the suffix -aga restricts this construction to a habitual/generic reading, just as in current Tanzanian Ndali, Kisi and Malila. In present-day Kinga, however, the configuration i(kʊ)-...-aga can only have a future-oriented meaning (Helen Eaton, p.c.). That is, it appears as if the exact semantic change that has been proposed above for Nyakyusa is documented for Kinga. Admittedly, given the scarce data, one cannot exclude the possibility that Wolff plainly overlooked the non-compositional semantics of the verbal configuration in question. This is what also happened in earlier descriptions of Nyakyusa (Schumann 1899; Endemann 1914), although an examination of texts from the same chronolect as these earlier descriptions (e.g. Berger 1933; Busse 1950) already clearly shows the same future-oriented semantics that are found in the present-day language.
The scenario argued for in this paper hinges on the assumption that a) the configuration kʊ-...-aga at an earlier stage of Nyakyusa had a habitual/generic meaning, and b) that the simple present kʊ-...-a at the same stage already allowed for the same reading as well as a progressive one. This situation, as attested in above mentioned languages of the wider area, by itself constitutes a puzzle: as discussed in §2.3. the prefix kʊ- is homophonous with the infinitival noun class 15 prefix, which is a strong indication of a former progressive periphrasis. Findings from grammaticalization theory (e.g. Bybee et al. 1994) would predict the acquisition of a habitual/generic reading as the direct result of semantic widening from progressive to imperfective without the need for an intermediate stage featuring an additional suffix, which furthermore is – in the present-day language – ambiguous between progressive and habitual/generic itself. As Sebasoni (1967) shows, what today is an inflectional morpheme in many Bantu language has most likely started out as a derivational suffix -ag with a pluractional meaning. A closer examination of both, the semantic shift that this suffix underwent, as well as the relative chronology of other diachronic changes in the field of tense, aspect and modality may thus shed light on this question.
Note that Haspelmath (1998) disregards a possible shift from habitual/generic to a future. While Haspelmath's reconstruction offers a solid explanation amongst others for the crosslinguistically recurring pattern in which habitual/generic and future (and possibly other specialized uses, e.g. narrative marker) pattern together or a future has a present tense meaning with certain verbs (see §1.2), in the case of the Nyakyusa construction in question we are dealing with a paradigm whose only meaning is that of a modal future. What is more, the above discussion has shown that a shift from habitual/generic to a future-oriented modal does not constitute that big a semantic leap. The scenario argued for in this study not only offers a semantic link between these two meanings without requiring an intermediate step from habitual/generic to irrealis (c.f. Fife 1990:178 on Welsh), but in doing so offers a motivated explanation for the non-compositional semantics of Nyakyusa kʊ-...-aga.
To summarize, this section has shown that the Nyakyusa verbal configuration kʊ-...-aga has a non-compositional meaning and expresses a modal necessity in the relative future. It has been shown that in three languages of the vicinity a comparable configuration enforces a habitual/generic reading on an otherwise ambiguous simple or imperfective present. An excursion into the semantics of habituals/generics has shown that these sentences are commonly understood as expressing modal necessity in the most normal worlds. This brings along a future-oriented implicature that creteribus paribus the depicted state-of-affairs will also hold in the future. It was then argued that the present-day meaning of the Nyakyusa modal future can be understood as the semanticization of the future-oriented implicature of a former explicitly habitual/generic construction.
In this paper, two verbal configurations in Nyakyusa have been discussed concerning their meaning and use and the possible developments leading to their present-day functions. The first constitutes a narrative marker, whose morphological composition clearly indicates a source in a verbal periphrasis that is widespread in Bantu as a present progressive or simple (imperfective) present. On the basis of Haspelmath (1998), it has been argued that its use as a narrative marker is the result of the grammaticalization of a new present, a side effect of which was the restriction of its predecessor to the specialized use in narrative discourse. The second verbal configuration consists of the new present plus a general imperfective suffix, which together yield a non-compositional future-oriented modal meaning. Drawing on data from Bantu languages of the wider area, in which a comparable configuration restricts an ambiguous simple present to a habitual/generic reading, as well as on a formal understanding of habitual/generics, it was argued that the modal meaning of this Nyakyusa configuration can be understood as a direct continuation of the universal quantification (hence necessity) of habituals/generics plus the semanticization of a generalized future-oriented implicature of the same.
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 I thank Sebastian Dom and the two anonymous reviewers for their insightful comments on an earlier version of this paper, Mary Chambers for proofreading and the a.r.t.e.s. Graduate School for the Humanities Cologne for funding my field research.
 As discussed by Carlson (2009), not all authors make a distinction between habitual and generic. Rather, they are mostly used as synonyms, with the choice of term depending on the linguistic tradition. Throughout this study, I will therefore speak of habitual/generic, the central point being that we are dealing with “'principled generalizations' […] not more 'accidental' facts“. (Krifka et al 1995: 44).
 There is debate, as to which of the two verbs, yor 'run' or dur 'stand', served as the auxiliary. The fact that we are dealing with a former periphrasis is, however, beyond doubt, as comparative evidence from other Turkic languages shows.
 For reasons of convenience, throughout this paper I will speak of a “narrative tense”, as is common in the Bantuist tradition (e.g. Rose et al 2002). Note, however, that we are not dealing with a tense in the deictic sense of the term (Comrie 1985).
 An anonymous reviewer pointed out Güldemann's (2003) discussion of progressives evolving out of predication focus constructions. Given the locative element, the well-attested grammaticalization path from locative to progressive (e.g. Bybee et al. 1994) provides a more straight-forward account for the initial grammaticalization of the construction in question. Furthermore, the focus of Güldemann's study lies on complex constructions in which a marker of predication focus suggests or enforces a progressive reading of an otherwise vague simple present. No indications fur such an origin are found in Nyakyusa.
Also, de Kind et al. (2015) investigate paradigms that stem from an identical or similar locative-based source structure in the Kikongo cluster of Bantu languages (H16). They show that the use of the locative infinitive constructions as a marker of predication focus is geographically more limited vis-à-vis the progressive reading and is only attested much later in the diachronic data. Also, in Kikongo focus-related uses only occur with the inversed word order auxiliary – locative infinitive. They conclude that the progressive reading thus constitutes the original one.
 As this paper focusses on the verbal word, contrary to Bantuist tradition morpheme-by-morpheme glossing is not applied within the noun phrase.
 This observation was first made by Heaton (2013). Following Botne (2010:43), perfective aspect is here understood as “an assertion about a time of the event subsequent to the endpoint of the event nucleus [the characteristic act encoded in the lexical verb, BP]”. This comes close to Welmer's (1974) completive and differs from the more wide-spread one in the literature on on aspect, according to which “perfectivity indicates the view of a situation as a whole, without distinction of the various separate phases that make up the situation” (Comrie 1976:16).
 An anonymous reviewer rightly questioned the translation of aasyele with an English pluperfect. The Nyakyusa verb syala is inchoative, that is, it encodes a resultant state of remainig as part of its lexicalized aspectual potential. Thus aasyele is more likely to be interpreted as 'was in a remaining state'. I have chosen a pluperfect translation, as the narrator presents this information with a slight delay. What is essential for the development of the storyline, and which becomes clear in the context of the entire narrative, is the fact that Mr. Tugutu himself does not move (instead he has placed fellow Tugutus along the track) while Hare is continually running.
 Eventualities that are closely linked together, e.g. cause and consequence are often, though optionaly, presented with the second one in a commutative infinitive.
 <mm> in the case of the noun class 1 object prefix indicates a long bilabial nasal.
 - anga is an allomorph of -aga preceding certain post-final clitics.
 i- before consonant-initial stems and ikʊ- preceding vowel-initial stems and object prefixes.

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