Aspectual auxiliary verbs in Xitsonga

In Xitsonga, certain Aspectual Auxiliary verbs (AA verbs) appear with double subject agreement. While these AA verbs have been reported in the description of Xitsonga (Baumbach 1987: 250-252), a systematic morphosyntactic study of these constructions has not been undertaken. This study aims to fill this gap. An AA verb is marked with tense, aspect, mood, negation and relative clause markers and may occur in wh-questions. The lexical verb following the AA verb may be the target of verbal extensions (applicative and reciprocal), reflexive, causative and passive markers.


Introduction
Consider the following sentences with and without the Aspectual Auxiliary verb (AA verb) dzumba 'always'.The auxiliary verb construction has two subject agreement markers, one before the auxiliary and one before the lexical verb.
ndzì dzúmbá ndzí nwá mátí 1SG ALWAYS 1SG drink water 'I always drink water' (literally, 'I always I drink water') The AA construction in (1b) is productive in Xitsonga (Marivate, Mathumba and Mabaso 1990: 22).However, descriptions relating to the kinds of morphosyntactic characteristics this construction has are insufficient.This paper aims to fill this gap by supplying data on various morphosyntactic constructions.
Complex verbal constructions, such as AA constructions, are not uncommon in Bantu languages.Gibson and Marten (2015) report that AA verbs inflect for temporal information in Swahili (2a), while lexical verbs may express aspectual information in Rangi (2b).In addition, double subject markers can be obligatory (Swahili and Rangi) or optional (siSwati).
siSwati ngi-ta-be ngi-tawu-nats-a 1SG-FUT-be 1SG-FUT-drink-FV 'I shall be about to drink' ngi-phindze ngi-m-fun-e 1SG-repeat 1SG-OM1-look.for-SBV'I look for him again' Xitsonga has siSwati-type AA verbs.In (3a) both the AA verb and the lexical verb is preceded by subject agreement.Some AA verbs are followed by the infinitive ku as in (3b).AA verbs can belong to only one of these two types.Here, we focus on the doubling type in (3a).
Type 1: doubling of the subject agreement Subject i -Aspectual auxiliary -Subject i -Lexical verb (in infinitive) ndzì dzúmbá ndzí nwá mátí 1SG always 1SG drink water 'I always drink water' (literally, 'I always I drink water') b.
Type 2: no-doubling of the subject agreement Subject i -Aspectual auxiliaryku -Lexical verb (in infinitive) hì tálá kú vá vóná làhà 1PL always INF OM3PL see here 'We always see them here.'(literally, 'We always to see them here ') In the literature on southern Bantu languages, AA verbs are also known as deficient verbs.Anderson (2011) reports an extensive survey of auxiliary verb constructions in African languages.In this report, Xhosa examples with AA verbs appear with the gloss CONTINUATIVE.Gibson and Marten (2015: 20) discuss AA verbs in siSwati (Taljaard Khumalo andBosch 1991, Ziervogel andMabuza 1976).Gibson and Marten also refer to studies of AA verbs in Zulu (Doke 1992: 202-214, Zeller 2006), Xhosa (du Plessis and Visser 1992) and Tswana (Cole 1955: 191, 236, 286).Following Nurse (2008: 29, 59), the AA construction can be classified as a two-word structure, and the AA construction in type 1 illustrated in (3a)is less common than type 2in (3b).Expanding from these previous studies, the current paper examines morphosyntactic characteristics (Nurse 2008: 43-46) of AA verb constructions.
Basic patterns of AA verbs in Xitsonga are presented in section 2. In section 3, grammatical structure associated with AA verbs are introduced, while grammatical structures associated with the lexical verbs are discussed in section 4. Additional structures are presented in section 5.

Basic patterns
Xitsonga AA verbs show a 'split/double inflectional' pattern (Anderson 2011: 42).It is split because tense, aspect, object and negative marking can appear with AA verbs, and it is double because of double subject agreement marking.The subject agreement preceding an AA verb and the following lexical verb must agree in person and number (4a-f).
Morphologically, the second subject marker copies the form of the first subject marking except in third person singular (4c), in which the second subject marker is marked with a (instead of a copy of u).
( It is odd to substitute the subject agreement of the lexical verb with the infinitive marker ku 'to' (6a).If the second agreement is ku, the verb dzumba must take an applicative suffix (6b), but the second agreement now cannot be the same as the first agreement (6c).
*ndzi dzumbela ndzi nwa mati 'I keep on drinking water' (similar to Type 2) Xitsonga has a number of AA verbs that belong to type 1 and type 2 as shown in (7).The meaning of these AA verbs often corresponds to aspectual, temporal or modal adverbs in English.The semantic characterisation of these verbs are based on Gibson and Marten (2015).
AA verbs may have a separate use as a lexical verb as shown in the last column of (7).The ✣ sign indicates words or meanings that do not appear in the Tsonga-English dictionary (Cuenod 1967).Examples of ✣ AA verbs are provided in the appendix.
(7) List of aspectual auxiliary verbs in Xitsonga (Baumbach 1987: 250-252) Next, we turn to the question of whether AA verbs form a single unit or whether they can be split by an intervening phrase.By default, the prepositional phrase (PP) na munghana 'with a friend' appears at the end of a sentence (9a).When this phrase is fronted, a pause is required after the phrase as in (9b).The phrase may follow AA verbs as illustrated in (9c), but a pause cannot be inserted.When there is a pause (marked by //) after the PP as in (9d), the AA reading is not available.Another diagnostic for the phrasal status of AA verbs comes from penultimate lengthening (marked with ː) at the end of a phrase.Expectedly, penultimate lengthening is required in (9b) before a pause; the absence of penultimate lengthening results in a prosodically ungrammatical sentence.Penultimate lengthening produces less categorical judgement than pauses; the presence of pause after PP is ungrammatical (9d), but the presence of penultimate lengthening is allowed (9c).*ndzi hatla na munghaːna // ndzi nwa byalwa (a pause // is prohibited) When an AA verb also has a meaning of a lexical verb, the sentence is ambiguous (10a).A pause after the PP only allows dzumba to be interpreted as a lexical verb (10b).
(10) The case of dzúmbà a. ndzì dzúmbá ná múnghánà ndzì nwà byàlwà ambiguous 'I am relaxing with a friend drinking beer' (dzumba as a lexical verb, default reading) 'I always drink beer with a friend' (also possible, as an AA verb) b.
ndzì dzúmbá ná múnghánà // ndzì nwà byàlwà only as a lexical verb 'I am relaxing with a friend drinking beer' '*I always drink beer with a friend' This section described basic aspects of AA verbs concerning the patterns of double subject markers, types of AA verbs and pauses in the AA construction.Section 3 examines various syntactic configurations that appear with AA verbs, and Section 4 presents constructions that can only appear with the lexical verb.

Aspectual auxiliary verb as a target
AA verbs are marked for tense, aspect, mood and negation.When AA verbs occur in a relative clause, the AA verb is marked with the relative clause marker.

Tense markers
The future tense marker ta appears before an AA verb as in (11a).This future marker cannot appear before the lexical verb (11b), nor can it appear before both verbs (11c).
*ndzi ta hatla ndzi ta nwa mati Yet, not all AA verbs are compatible with the future tense ta.AA verbs that make specific reference to the past cannot be used with the ta tense.Future tense can be used with AA verb as in (12a) and (12b).However, the AA verbs in (12c, d) denote an event in the past; they cannot co-occur with the future tense marker ta (the same restriction holds for khanga 'once' and zanga 'never').
( *va ta kanga va nghena kereke 3PL FUT never 3PL enter church (Intended: they will never enter the church)

Aspect markers
In Xitsonga, aspects such as perfect, progressive and persistive are also marked on the AA verb, different from the language reported in Gibson and Marten (2015), in which aspect markers appear on the lexical verb.
The perfect/past tense suffix -ile is attached to the AA verb (13a The -ile suffix can denote simple past as well as perfect tense.The phrase hi nkarhi wolowo 'at that time' can be used as a diagnosis for simple past ( 14). ( 14) Simple past with -ile hì hàtl-ílé hí dyá vúswà hì nkàrhí wólówó 1PL quickly-PST 1PL eat porridge at time that 'we quickly ate porridge at that time' The phrase 'since my childhood', which denotes an event continuing from the past, can be used to diagnose the perfect use of the -ile suffix as in (15).( 15 *a hi hatlangi hi dyile vuswa hi nkarhi wolowo '(intended) we did not quickly eat porridge at that time' The past negative without the -ile suffix is ambiguous (27a) unlike affirmative sentences.Both the simple past phrase 'at that time' (27b) and the perfect phrase 'since yesterday' (27c) can be used with the past negative construction.
à hí hàtl-àngì hì nwà màtì kù sùkèlà tòlò NEG 1PL quickly-PST.NEG 1PL drink water since yesterday 'we have not quickly drunk water since yesterday' While the -ile suffix can co-occur with the past negative construction, the future marker ta cannot co-occur with the future negative construction (28).6 (28) Future negation cannot co-occur with ta, the future marker *a ndzi nge hatl-i ndzi ta nwa mati NEG 1SG FUT.NEG quickly-NEG 1SG FUT drink water 'I will not quickly drink water' The example (29) shows that the copular verb ri 'to be' is a lexical verb in the AA verb construction.

Other constructions: relative clauses and wh-questions
The relative clause marker in Xitsonga relative clauses agrees with the head of the relative clause.The lexical main verb of the relative clause is then marked with the -ka suffix as in (33a).When used in a relative clause, the -ka suffix attaches to the AA verb (33b, d), not the lexical verb (33c).
váná lá-vá hátlá-ká vá dyá vúswà vá lává kú tlángá éhàndlè children REL-CL2 quickly-REL SM2 eat porridge SM2 want to play outside 'children who quickly eat porridge want to play outside' Subject wh-questions in Xitsonga, as in other southern Bantu languages, require the question word (mani 'who') to be fronted (see Zerbian 2007: 69-71 for similar discussions).The verb of the subject wh-question is also marked with the suffix -ka.This suffix -ka must attach to the AA verb (34a, d), and cannot be attached to the lexical verb (34b), nor can it appear on both verbs (34c).
í mánì á hàtlà-kà à dyà vúswà?FOC who 3SG quickly-KA 3SG eat porridge 'who does quickly eat porridge?' In situ object wh-questions do not require the -ka suffix on the verb (35a).When the object wh-word is fronted, the main clause shows the morphosyntax of a relative clause with the suffix -ka.A resumptive pronoun appears in the original place of the fronted wh-words.This -ka suffix attaches to the AA verb (35b), and not the lexical verb (35c).The same pattern is shown when the wh-word 'which one' is fronted as in (35d).
( In this section, morphosyntactic processes that target the AA verb were presented.Tense, aspect and mood markers all attach to the AA verb.In negative sentences, the -ile suffix may attach to the lexical verb and produce a perfect reading; simple past is not a possible interpretation when the negative perfect/past marker co-occurs with the -ile suffix.When the lexical verb is the copular verb ri 'to be', negation can target either the AA verb or the copular verb.These alternatives create a scope interaction in the interpretation of the sentences.Theka suffix that appears in relative clauses and wh-constructions also targets AA verbs.
The patterns in this section suggest that AA verbs are placed in a syntactically higher position than lexical verbs.The pattern in which the negative suffix can attach to AA verbs or lexical verbs further suggests that AA verbs are in an even higher position when the negative suffix is attached to it; it probably shows a type of NEG raising.In the following section, morphosyntactic phenomena that target the lexical verb will be presented.

Lexical verb as a target
In this section, we examine morphosyntactic processes that target the lexical verb in AA constructions: object marker, verbal extensions (applicative, reciprocal, causative and passive) and reflexive marker.Data that is reported here includes the doubling of the object marker and that of the causative and passive markers.

Position of object pronoun and reflexives
In AA constructions, the object pronoun is placed between the second subject agreement and the lexical verb (36a).The object pronoun cannot be placed before the AA verb (36b), but it may be doubled (36c).The doubling of object pronouns adds an emphatic meaning to the sentence targeting the object pronoun (translated as 'definitely' in the examples in ( 36)).In (36d-h), each example has a pair of sentences: object marker before the lexical verb and the doubling of the object marker.
( When the object marker is doubled (37a), it cannot occur with the modal verb fanele ku 'must' (37b).For reasons beyond the scope of this paper, the doubling is not possible when the lexical verb xeweta 'to greet' is used by itself (37d).However, the addition of the locative adjunct exikolweni 'at school' allows object markers to double (37e).( 37 The reflexive prefix ti-also attaches to the lexical verb (38a, b).The reflexive prefix cannot attach to the AA verb (38c), nor can it occur on both verbs (38d).

Verbal extensions
Xitsonga has verbal extensions that change the argument structure of the lexical verb.The applicative suffix -el-, when attached to the lexical verb (39a), for example, makes the verb take the benefactive object mánáná 'mother'.In AA constructions, this suffix does not attach to the AA verb (39b), nor can it double as in (39c).When the AA verb hatla 'quickly' (or any other AA verbs) functions as a lexical verb, the addition of the applicative suffix is possible: hatlela 'to move fast' (39d), with the ku clause that denotes purpose; the purpose clause part is different from type 2 in (3b).Doubling of the subject agreement is not possible when hatla is a lexical verb (39e).
( The passive suffix in Xitsonga is attached to the lexical verb (41a, c).It is ungrammatical to attach the passive suffix to the AA verb (41b, d).
The causative suffix -is-attaches to the lexical verb (42a), and it does not attach to the AA verb (42b).When hatla is a lexical verb, the causative suffix can attach to it (42c).Doubling of the subject agreement is not allowed because it will result in a structure, which is ungrammatical (42b).
ndzì hàtl-ìs-à kù nwá mátí 1SG move.fast-CAUS-FVINF drink water 'I make a fast move to drink water' (= 'I quickly drink water') The passive suffix can be doubled; it attaches to the lexical verb and to the AA verb (43).Likewise, the causative suffix can also double (44).However, the doubling of the passive or causative suffix does not have any emphatic effects on the meaning of the sentences, unlike the doubling of object pronouns.

5.
Yes-no questions, comparatives and stacking The Q-morpheme for a yes-no question in Xitsonga is xana.Adding the Q-morpheme to a declarative sentence turns it into an interrogative sentence (45).
( The position of the Q-morpheme is relatively free.In addition to the front of a sentence, the Q-morpheme can be placed after the AA verb (46a), after the lexical verb (46b) or at the end of a sentence (46c).However, the morpheme xánà cannot be placed immediately after the subject agreement markers (46d, e), which suggests that subject markers in Xitsonga are really preverbal prefixes, even though they are written disjunctively.This distributional restriction of xánà suggests that the agreement marker and the following verb form a constituent that cannot be separated.
( Stacking of adverbial auxiliaries is also possible.In ( 48), examples with two adverbial auxiliaries (hatla 'quickly' and engeta 'again') are shown.The order of these auxiliaries determines different scopes of AA verbs.In (48a), hatla has a wider scope.The sentence emphasises the quickness in which water is being drunk compared to the recurrence of the drinking event.The AA verb engeta has a wider scope in (48b), in which the emphasis is on the recurrence of the drinking event rather than the quickness of the drinking of the water.*ndzi hatla ndzi engeta ndzi tlhela ndzi nwa mati f. *ndzi engeta ndzi hatla ndzi tlhela ndzi nwa mati Extensions can also be stacked: the passive marker follows the applicative marker.In such a case, either the verbal object mati 'water' (50a) or the applicative argument manana 'mother' (50b) can be the subject of the passivised lexical verb.
mánáná ú hátlá á nw-ér-íw-á mátí mother SM3SG quickly SM3SG drink-APPL-PASS-FV water 'Mother is quickly drunk water for' In the passive sentences, doubling of the passive suffix is also acceptable as shown in (51).However, the doubling does not result in emphasising any parts of the sentence.
mánáná ú hátl-íw-á á nw-ér-íw-á mátí mother SM3SG quickly-PASS-FV SM3SG drink-APPL-PASS-FV water 'Mother is quickly drunk water for' The causative marker precedes the applicative marker (52a).When an AA verb is added to the sentence (52b), the doubling of the causative suffix is possible (52c).Note that causative precedes applicative, whereas passive follows applicative.While the passive marker and the causative marker have a different syntactic location, their doubling is grammatical.

Discussion and conclusion
In this paper, we presented the distribution of AA verbs in Xitsonga.
These two sentences are grammatical if ta is the lexical verb ku ta 'to come' as shown below. 3 ).The -ile suffix cannot attach to the lexical verb (13b), nor can it appear in both positions (13c).
Progressive in Xitsonga is marked with a periphrastic construction: le ku V-eni (ka) as in (18a).This progressive is marked on the AA verb (18b), and it cannot attach to the lexical verb (18c).Negation is marked on AA verbs.The auxiliary verb hatla 'quickly' is negated in three tenses below: present negative (25a), perfect negative (25c) and future negative (25e).Negative markers may not attach to the lexical verb (25b, d, f).
*ndzi hatla ndzi le ku nw-eni ka mati Persistive aspect is expressed by the complex form: -a ha ri ku V-eni.This aspect marker also attaches tothe AA verb (19a).It cannot attach to the lexical verb(19b).*ndzi hatla ndz-a ha ri ku nweni ka byalwa More examples of the persistive marker -a ha-'still' are shown in (20).The third person singular subject wa is a contracted form of u and a. 4 *ndzi hatla ndzi fanele ku nwa mati Optative in Xitsonga is constructed as a SBJ V-e(ni), and is marked on the AA verb (24a, c, d, e).*ndzi hatla a ndzi nge nwi mati In affirmative sentences, the perfect/past suffix -ile must appear on the AA verb.In negative sentences, the -ile suffix can appear on the lexical verb (26a, b) in sentences that denote the perfect tense only.Adding a simple past phrase such as hi nkarhi wolowo 'at that time' to (26a, b) results in ungrammatical sentences as shown in (26c) and (26d), respectively.
Do you always see an elephant in the Kruger?' (or dzumba as a lexical verb 'Do you relax and see an elephant in the Kruger?') Stacking of three adverbial auxiliaries is also possible.As shown in (49), the stacking does not necessarily result in a change of meaning.However, not all orders are possible.The auxiliary verb ku tlhela 'once' cannot be the last of the three verbs (49e, f).A study of restrictions regarding surface linearisation of AA verbs is a topic for future work.(49)Stacking of three adverbial auxiliaries a. ndzì tlhèlà ndzí hátlá ndzí èngètà ndzì nwà màtì 1SG once 1SG quickly 1SG again 1SG drink water 'Once again, I quickly drink water again' b. ndzì hàtlà ndzí tlhélá ndzí éngétà ndzì nwà màtì c. ndzì tlhèlà ndzí éngétá ndzí hàtlà ndzì nwà màtì d. ndzì èngètà ndzí tlhélá ndzí hàtlà ndzì nwà màtì e.
Various morphosyntactic structures suggest that AA verbs and lexical verbs show complementary distribution.The table in (53) is a summary of all the patterns.Parentheses show the loci of interest for future research regarding AA constructions in Xitsonga.A cross-linguistic study of other southern Bantu languages such as TshiVenda, Setswana, SiSwati, Sotho, isiZulu, isiXhosa, etc. is also warranted.(53)Summary of morphosyntactic characteristics of AA verbs and lexical verbs