The Multiple Syntagmatic Positions and Various Meanings and Functions of the Morpheme Nga in Bantu

Alexandre Kimenyi
kimenyi@saclink.csus.edu
California State University at Sacramento
32rd ACAL Berkeley

O. The morpheme nga which is realized as -ang- in the suffix position but as -nga- or -nge- elsewhere, like the perfective morpheme -ile, the past tense -a-, the reciprocal -an-, the consecutive/narrative tense -ka-, the applicative -ir-, is found in the majority of Bantu languages. What differentiates it from others, however, is its different meanings and functions and its various syntagmatic positions in the verb structure.These meanings and functions include acting as an auxiliary verb, a presentative, an exclamation, an intensifier, a frequentative, an emphasizer, a complementizer, a habitual/imperfective marker, a negative, etc. Besides appearing as a free morpheme, nga occurs in the various positions of the verbal architecture as a preprefix, a prefix, a stem, a suffix, or a postsuffix. It is also used as a derivational suffix. The metonymic association among these meanings and its near phonetic identity argues strongly for its polysemous nature rather than being different morphemes which happen accidently to tool alike.The polysemous nature of this morpheme as well as its various structural positions are found not to be unique because of the existence of other morphemes within the same linguistic family which behave exactly the same. This phenomenon which is difficult to handle in mainstream structural-generative framework is indeed normal and found in other languages as well and is expected and explainable in Peircian semiotics and grammaticalization theories.

1.1. "NGA" as a free morpheme

As a free morpheme "nga" is used in Kinyarwanda as a presentative or an emphasizer. In both cases, it is found with demonstrative pronouns, only.

As a presentative, nga lengthens the initial vowel of the demonstrative and assigns a high tone to the nucleus of the following syllable.This is shown in (1).

1. uyu 'this'> nguuyú 'here s/he is'
aba 'these'> ngaabá'here they are'
aha 'here'> ngaahá'here is the place'
aho'there' > ngaahó 'there is the place'
icyo'that' > ngiicyó 'there it is'
uríiya 'that one' > nguuríiya 'there s/he is'
báriíya 'those ones' >ngaabáriíya 'there they are'

The presentative is used as a response to such questions as where is "X"?

As an emphatic morpheme, it occurs inside a reduplicated demonstrative. A high tone is assigned to the initial vowel of the second demonstrative and to the first mora of the following syllable as is illustrated in (2).

2.uyu'this' > uyu ngúuyú 'this one'
aba 'these' > aba ngáabá 'those ones'
aho 'there' > aho ngáahó 'there'
icyo 'that' > icyo ngíicyó 'that one'
ubu 'now' > ubu ngúubú 'right now'
In Luganda, nga as a free morpheme is found before adjectives or verbs as an exclamation marker as shown in (3) or as a complementizer as examples in (4) show.

3. nga kirungi! 'very good'
nga nkola. 'me working'
ng'olabye 'you are in trouble!'
ng'oyambadde 'you are well dressed!'

4.nakulaba ng'oleeta ebitabo.'I saw you bringing books'
nabalaba nga baleeta ebitabo. 'I saw them bringing books'
nabalaba nga muliira mu luguudo.'I saw you eating in the street'
nabalaba nga baliira mu luguudo. 'I saw them eating the street'
namulaba ng'ayogera Oluganda. 'I saw him speaking Luganda'
namulaba ng'ayambadde engoye eziddugala
nabalaba nga bambadde engoye eziddugala
lwaki wabadde ng'oliira mu luguudo? 'why were you eating in the street?'
lwaki wabadde ng'oyambadde engatto? 'why were you wearing shoes?'

As a complementizer, nga in most of the cases introduces participial clauses. Luganda has other types of complementizer morphemes.

In Zulu, as a free morpheme "nga" acts as either a preposition (5) or a copular (6).

5. ngemoto /nga-imoto/ 'by car'
ngendiza /nga-indiza/ 'by plane'
ngomkhumbi /nga-umkhumbi/ 'by boat'
sibhala ngepensele 'we write with a pencil'
halala ngosuku (nga-usuku) lokuzalwa kwakho 'congratulations on your birthday'
6. ungudadewethu 'she is my sister'
ungumfewethu 'he is my brother'
ungubaba wami 'he is my father'
bangamazulu 'they are Zulu'
ngamanzi 'it is water'

Like in Zulu, the morpheme "nga" is used in Shona as a preposition also:

7. titaurirenyi ngegadheni renyu. 'tell us about your garden'
tell-us about-garden of-you
titaurirenyi ngemombe dzenyu. 'tell us about your cows'
titaurirenyi ngehuku dzenyu. 'tell us about your chickens'

2. "NGA" as a stem

In some languages, "nga" is used as verb stem, thus having its own affixes. Shona is a good example.

1. Iye wakange ari kutsvaka basa. 'She is looking for work.'
s/he s/he-aux s/he-be look work
Ndakange ndisati ndaziva kuti mwaida musikana.
I-pst-aux that you-wanted girl
'I didn't know that you wanted a gird.'
Ndanga ndichifunga kudaro.'I thought so'
I-aux I-think so
Mbatya dzevana hadzisati dzasvipa, asi dzinonga dzasvipa manheru.
clothes of-children are-not-yet diry but they-t-aux dirty evening
'The children's clothes are not dirty yet, but they will be dirty by this evening'.
Ndakaona munhu wakange ari kurima. 'I saw the person who had been ploughing'
I-saw person s/he-aux s/he-be cultivate
Ndiani wakange ari kurima? 'Who had been ploughing?'
who she-aux s/he-be cultivate
Wakange asingagoni kutibatsira. 'He wasn't able to help us'
s/he-aux s/he-not-can to-us-help
Wanga asingadi kuenda. He doesn't want to go.
s/he-aux s/he-not-want to-go
Vanozonga vasvika. 'They will have arrived.'
they-t-aux they-arrive
Zuva rinonga risingachapisi. 'The sun is no longer hot (doesn't burn anymore)'
sun it-t-aux it-not-t-burn

"nga" as examples above show is an auxiliary verb which has its own tense markers, aspect markers, etc. but cannot have object pronouns or verbal extensions.

3. "NGA" used as a preprefix.

The morpheme "nga" appears as a preprefix as well. This is shown by examples from Shona and Kindendeule. In Shona as shown in (1), it is a hortative marker

1.ngatidye. 'let's eat'
ngatiende kumusha.'let's go home'
let's-go home
matombo ngaabviswe. 'let the stones be removed'
stones they-should-be-removed
ngatiise hari pachoto. 'let's put the pot on fire'
let's-put pot on-fire
Vapwere ngavagare pasi. 'let the children sit down'
children they-should-sit down
Nzungu ngadzikangwe. 'let the groundnuts be roasted'
groundnuts they-should-be-roasted
Ivu ngarienzaniswe.'let the soil be leveled'
soil it-should-be-leveled

Kindendeule like Kiswahili uses nga for conditionals. Unlike Swahili, however, where this morpheme appears as a prefix, in this language it is used as a preprefix.

2. bageni nga-ba-hik-a leleno, nga-ti-li mbuhi
guests cond-they-arrive-asp today cond-we-eat goat
'If the guests had arrived today, they would have eaten a goat'.

4."NGA" used as a prefix

The morpheme "nga" is used in many Bantu languages as a prefix with different meanings and functions.

In many languages, it has a potential meaning. This is illustrated by the Zulu, Shona, Chilungu and Namwanga examples.

Zulu.

1. Singaoda manje? 'May I order now?'
1st neg-nga-order now
Ngingabhema laha na? May I smoke here?'
I-nga-smoke here Q
Ungahamba manje.'You may go now'
You-nga-go now
Ujojo angahamba manje na? 'May Georges go now?'
Georges he-nga-go now Q
Umfana angangena na? 'May the boy come in?'
boy he-nga-com-in Q

Ungehambe manje Jonas. 'You may not go now, Jonas'
Ungengene lapho Catherine. 'You may not go there Catherine'
Ungebheme lapha baba. 'You may not smoke here, father

Shona

2. Ndingamuona here manheru ano? Can I see her this evening?
I-nga-him/her-see evening this
Ndingamudaidze kuti muchida kumuona. 'I can call her if you want to see her'
I-nga-him/her-call if you-want to-him/her-see
Ndinoda musikana angandibatsire kubika nekuchisa.
I-want girl she-nga-me-help to-cook and-to-iron
'I want a girl to help me cook and iron'
Zvitambi ndingazviona papi? 'Where can I get stamps?'
stamps I-nga-them-see where
akaenda ndingaendawo. 'If s/he goes, I can go also'
s/he-t-go I-nga-go-also
akasaenda handingaendawo. 'if she doesn't go, I can't go, either'
s/he-t-neg-go neg-I-nga-go-also

In Chilungu and Namwanga (Bickmore, 2001), -nga- used as prefix is a potential marker.

Namwanga:

3. tu-ngá-mú--sakul-il-á
we-t-we-him/her-comb-appl-asp
'we can comb for him/her'.

Chilungu:

4.tuu-ngá-mú-ziik-il-á
we-t-him/her-bury-app-asp
'we can bury for him/her'
tu-ngá-súkul-il-á
we-t-accompany-appl-asp
'we can accompany'

tu-ngá-mú-ful-il-á
we-t-him/her-wash-appl-asp
'we can wash for him/her'
tu-ngá-sópólolol-el-á
we-t-undo-appl-asp

In Kindendeule, Ngonyani (2001) nga used as prefix refers to the "not yet tense".

5.a-nga-tol-a ugembe
s/he-t-take-asp beer
"s/he has not taken a beer yet".
"lest s/he should taken the beer".

bageni ba-nga-hik-a leleno.
guests they-t-arrive-asp today
"the guests have not arrived today".
"lest the guests should arrive today".

In Kiswahili, it is realized as -nge- in the realis conditional and -ngali- in the irrealis conditional in both the apodosis and protasis.

6. Tungekuwa na pesa nyingi, tungenunua nyumba ile. 'If we had a lot of money, we would buy that house.'
Ungeliakwa kwao, ningekushonea gauni. 'If you were invited at their place, I would make you a dress.'
Asingesoma magazeti asingejua mambo hayo. 'If s/he didn't read the papers, s/he would not know the news.'
Nisingekuwa na pesa nyingi ningekaa shamba. 'If I didn't have a lot of money, I would live in the countryside.'

7. Ningalimwona, ningalipata habari hizo. 'If I had seen him/her, I would have gotten that information'
Kama ungalikuwapo ungalimsaidia. 'If you had been there, you would have helped him/her'.
Tusingalikwenda huko, tusingalimwona rais. 'If we had not gone there, we would not have seen the president.'

5. "NGA" as an inflectional suffix

"NGA" is also used as an inflectional suffix with different meanings such as imperfective aspect marker, a habitual, a negative, etc.

In Zulu, it acts as a negative as shown in (1).

1.angazanga 'I didn't know'
I-don't-know-anga
abantu ababuyanga 'the people didn't come back'
people didn't-come-anga
inkosi yenkantolo ayivumanga 'the magistrate did not agree'
chief of court he-didn't-agree-anga
uFred akafikanga. 'Fred didn't not come'
Fred he-didn't-arrive-anga

In Luganda, it is a progressive

2.baakolanga. 'they used to work'
nnaasomesanga abaana. 'I will be teaching children'
nnaanyumyanga mu Luganda. 'I will be speaking in Luganda'
nnaalyanga amatooke. 'I will be eating bananas'
nnaakyaliranga 'I will visit'

3. temukuleetanga bitabo mu kibiina.'never bring books into class'
temukuutanga kikeerezi mu kibiina. 'never get to class late'
temwogeranga Luganda lusobu. 'never speak bad Luganda'
temwambaranga ngoye ziddugala.'never wear dirty clothes'
temuliiranga mu nguudo. 'never eat on the streets'
tetukolanga ki? 'what shall we do?'

In Lunda, as a suffix -nga shows a habitual or a continuous event.

W-a-zat-anga nakanshi
s/he-t-work-Hab a lot
's/he works a lot'

Wayíléenga kumuha nabudidi.
w-a-y-íli-anga ku-muha na-budidi
s/he-t-go-rp-imp loc-fields in-morning
's/he used to go to the fields'

W-áka-yá-anga.
s/he-fut-go-impf
's/he will be going'

N-a-humaˆnana ibwambu dami ni-n-a-nayanga ku-kalonga
I-pst-meet friend friend of-me when I-pst-go-impf to-river
'I met my friend when I was going to the river'

6. "NGA" used a derivational suffix

As derivational suffix, nga has various meanings such as iterativity, frequentativity, intensification, repetitivity, quantification, etc. In Kinyarwanda it is used mostly with sound and movement verbs as examples in (1) indicate.

1.kudédemaanga 'to mumble'
gucúraanga<gucura (to forge)'to play the cithare'
kwáamaanga 'to cry a lot'
kudáanyaanga 'to talk nonsense'
kuvúga<kuvúga (talk) 'to say anything that comes in the head'
kuzímaangwa<kuzímura (tell secrets) 'to be indiscreet'
kuréeshaangwa 'to talk nonsense'
kubwéejaanga 'to bark'
gukácaanga 'to chew'
gukómaanga 'to knock at the door'
kwíirukaanka <kwíiruka (to run) 'to run'

More examples from Kinyarwanda are given in (2) to show the different meanings of this morpheme.

2. kwaanguhaanga<kwaanguha (be disloyal) 'to be alright'
kwáasamaanga<kwáasama (open the mouth) 'to open the mouth repetitively'
kudoomaangira 'to be too full and become unable to move'
kudoondaanga <kudoonda (picket) 'to peckot non stop'
gufufumaanga 'to swell a lot'
kugoramaanga<kugorama (be crooked) 'to be crooked'
guhiinyaanga <guhina (fold) 'to squeeze with a lot of energy'
kuremaanga< kurema (to create) 'to make something which is not perfect'
gushimaanga <gushima (to scratch) 'to stratch repetivively'
gusibaanga <gusiba (erase)'to erase with force or repetitively'
gusiribaanga<gusiriba (destroy) 'to destroy'
gususumaanga<gususumira (tremble/shake) 'to shake'
gusútamaanga<gusútama (to sit on one's heels) 'to sit uncomfortably for a long time'
gutérekaanga<gutéreka (to place things) 'to place things in a disorderly manner'
gutobaanga <gutoba (to muddy) 'to muddy repetitively'
kuzaanga <kuuza (ruminate) 'to ruminate continuously
kuménaanga < kuména (to break) 'to break into many pieces'
kurúmaanga<kurúma (to bite) 'to eat solid food without any drink or relish'/ 'not to find water to drink (cows).

Some of the meanings of the suffix -ang- are rendered by reduplication in Kinyarwanda as shown in (3).

3 kurébareba<>kurébaanga
kudáamadaama<>kudáamaanga

In many cases, the morpheme comes with the reciprocal morpheme -an-

4. gusíbaanganya<gusiba (erase) 'to erase completely'
gucúmaanganya 'to create a disorder'
gusáraanganya 'to share'
kuzímaangana<kuzíma (distinguish/exerminate) 'to exterminate completely'
gukómaangana<gukóma (to talk) 'to collide and make noise'
kurímaanganya<to tell lies
kudúduunganya/kudúdoonganya 'to roar/reprimand'
gucúbaangana 'to move inside a container (liquid)'
kudábaangana 'to move inside a container (liquid)'
kwíiyumaanganya < kwúma (get dry) 'to be patient'

In this way, Kinyarwanda behaves exactly like Yao. Most of the cases where nga appear as a suffix, in Yao it comes with the reciprocal morpheme -an- or reversal morpheme -ul-.

5. -ut- 'pull' -utang- 'pull for a long time'
-jaas- 'throw' -jaasang- 'throw around/scatter'
-jiit- 'sprinkle' -jiitang- 'sprinkle around'/pour out'
-miis- 'scatter seeds' -miisang- 'scatter seeds in all directions'
-tw- 'pound' -twang- pound
-jaul- 'go' -jaulangan- 'go off at once'
-lek- 'leave' -lekangan- 'depart from one another'
-ik- 'arrive' -ikangan- 'come together in larger numbers'

6. -tem- 'cut' -temangul- 'break up things'
-pees- 'make an opening' -peesangul- 'make an opening thoroughfly'
-timb- 'push/butt' -timbangul- 'push hard'
-sap- 'tease cotton' -sapangul- 'unravel'

7. "NGA" used as a postsuffix

In Setswana, the relative marker is marked in spelling by a prenasalized velar voiced stop (ng) at the end of the finite verb. This has definitely has to be the morpheme -nga. Data are taken from (Creissels, 2001).

batho ba-lem-ile tshimo
people they-cultivate-asp field
'The people have cultivated the field'

tshimo e batho ba-e-lem-ile-ng
field it people they-it-cultivate-asp-rel
'the field that people cultivated'

batho ba-ne ba-lem-ile tshimo
people they-aux they-cultivate-asp field
'the people had cultivated field'

tshimo e batho ba-ne-ng ba-e-lem-ile
field it people they-aux-rel they-it-cultivate-asp
'the field that people had cultivated'.

8. Reconstructing 'nga'.

Like the majority of other tense markers as examplified by the Swahili case, nga must come from a verb. Its reflexes are still found in Shona, as we have already noticed where it acts as an auxiliary or as a free verb meaning 'to be' or 'be like' and in Kinyarwanda. In Kinyarwanda, the Shona cognate is realized as kungana [kuungana] 'to be equal/to have the same size or age'.

Aba báana ba-raa-ngan-a. 'These children have the same age/have the same size.'
these children they-pres-be equal-asp
Abo báana baa-ngan-a báte? 'How old are those children?'
those children they-have the same age-asp

The Kinyarwanda verb may be a combination of both the stem -ng- and the reciprocal/comitative morpheme -an-, since as we have observed earlier in Kinyarwanda and Yao, the suffix -an- is sometimes added without meaning change when
-ang- is used as a derivational suffix.
I think, however, that the right protoform might be the Kinyarwanda form -ngan-, because monosyllabic verbs which happen to be a very small number were also bisyllabic
but later on became monosyllabic because of being older, being more used and becoming function words thus resulting in phonetic shrinking.

II. Morphemes which behave like nga

There are other morphemes which behave exactly like the morpheme "nga' thus occupying different syntagmatic positions in both the sentence structure and the verb architecture and having different meanings and functions as well. Some of these are the copular ni, the negative morpheme, the reciprocal/comitative morpheme and the prepositions ku and mu.

1. The copular ni

The copular ni is widespread in Bantu languages. Besides being used as an independent morpheme, it is found as a verbal preprefix.

1. Yohaáni ni umugabo.'John is a man'(Kinyarwanda)
ni jyeewé wahamágaye. 'I am the one you called'.
be me you-called
2. Mtoto ni mbaya. 'The child is bad' (Kiswahili)
Ni wewe. It is you

As a preprefix, it is used with verbs in the subjunctive form to express an immediate action in Kinyarwanda.

3. nimusomé.'read now' <> musomé 'you should read'
nibageendé.'they should go now'<>bageendé 'they should go'

With present and future tenses, it has the meaning of "if" or "when"

4. ní-ba-som-á kíno gitabo u-m-bwiír-e. 'Tell me if/when they read this book'
ni-they-read-fv this book you-me-tell-fv

ní-ba-geend-á ba-ku-bwiír-e ahó ba-gii-yé.
ni-they-go-fv they-you-tell-fv where they-go-asp
'If/when they leave, they should tell you where they are going'

ní-mu-záa-geend-a, mu-záa-tu-meny-eesh-e. 'If/when you will go, let us know.'
ni-you-fut-go-fv you-fut-us-know-cause-fv

In other languages, when ni is used as a preprefix, it functions as focus marker as the following example from Chaga-Kivunjo shows (Moshi, 2001).

5. náwétéma
ni-á-wá-é-téma
foc-s/he-asp-fut-play
'she would have played.'

The case marking role of ni in Kinyarwanda and in Kiswahili probably came from the copular also. In Kinyarwanda, this ni acts as prefix with certain nouns to show time.

6. nînjoro 'in the evening'<> ijoro 'night'
nímugórooba 'in the evening'<> umugórooba 'evening'
nímuúnsi 'in the evening'<> umuúnsi 'day'

In Kiswahili, it is affixed to any noun to show location.

7. ni saa moja 'it is seven'
nyumbani 'home'<> nyumba 'house'
mezani 'on the table'<>meza 'table'

In Kiswahili and other languages such as Shona, it is suffixed to the imperative form of the second person plural.

8. karibuni 'come in'<> karibu
someni 'read' <> soma

2.2. The negative morpheme

The negative marker, also,appears as a free morpheme, a preprefix, a prefix or a suffix.
Bantu languages have different types of negative markers which many times occur in complementary distributions as shown in the Kinyarwanda examples provided below. The negative marker for verbs in the main clause is the prepreix nti-. The subordinate clause negative morpheme is the prefix -ta-. The immediate command negative morpheme is the prefix -ii-, the existential negator is nta whereas the negative copular is si.

1. baasomye 'they read'<> ntibaasomye'they didn't read.'
bazaavuga 'they will talk'<> ntibazáakóra 'they won't talk.'

It is also interesting to note that the first person negative marker is not nti- but si- in many languages:

2. sii-n-som-a 'I am not reading' (Kinyarwanda)> si-som-i 'I don't read' (Swahili)
*nti-n-som-a *ha-ni-som-i

nta as a non-existential morpheme is the counterpart of the existential morpheme hari in both meaning and structure:

3. ha-ri umuuntu u-rí ku ruugi. 'there is somebody at the door.'
there-is person who-is on door
ntaa muuntu u-rí ku ruugi. 'there is nobody at the door.'
there-is-not person who-is on door

ha-ri ahó n-gii-yé. 'I am going somewhere.'
there-is where I-go-asp
nta ho n-gii-yé. 'I am not going anywhere.'
there-is-not where I-go-asp

ha-ri a-ba-sóm-a. 'there are those who are reading.'
there-are aug-they-read-asp
ntaa ba-sóm-a. 'there are none who are reading.'
there-is-not they-read-asp

The subordinate clause negative marker (conditionals, relatives, completives,...) is -ta-.

4. abáana baboná néezá 'kids who can see well'
abáana bataboná néezá 'kids who don't see well

There are other languages which have distinct main clause and subordinate negative markers also as

In Kuria (Güldemann, 1999)

5. ba-ta-mo he.
they-neg-be-in neg
'they are not within.'
nte ba-mo he.
neg they-be-in neg
'they are not within.'

Luganda:

6. té-báawa báana bitábo
neg-they-give children books
'they didn't give books to the children.'

té-yalába mwáaná nga agúlá é-bítábó.
neg-s/he-see child comp s/he-buy books
's/he didn't see the child buy books.'

t-ámanyí bakází bagulá bíkópo bitonnya.
neg-s/he-knows women who-buy cups that-drip

amanyi ábakázi abátágúla bikópo bitonnya.
s/he-knows women who-neg-buy cups that-drip
's/he knows women who don't buy cups that drip.'

In some other languages such as Zulu and Shona, the subordinate negative marker is -si- which without any doubt is the negative copular si.

The main clause negative marker and the non-existential morpheme in Kinyarwanda are probably a combination of the copular ni andthe subordinate clause negative marker -ta-.
This analysis is not farfetched because the first person negative looks exactly the same as the negative copular si. This phenomenon is found in many Bantu languages as the Swahili and Kinyarwanda examples illustrate.

7. siinsomá 'I don't read' (Kinyarwanda) sisomi 'I don't read'
ntidusomá 'we don't read' hatusomi 'we don't read'
ni igitabo 'it's a book' ni kitabu 'it's a book'
si igitabo 'it's not a book' si kitabu 'its' not a book'

In Kinande (Progovac, 1993), it is this negative copular which is used as a verbal preprefix negative marker.

8. yoháni anzíré omukáli. 'John likes the woman.'
John likes woman
yohání sí ánzire omúkali. 'John doesn't like the woman.'
John neg likes woman

The non-prenasalized form -ta- which is realized as -ti- or -te- in other languages comes probably form the verb -ti 'to say' which in many languages serves as a complementizer and in some as a negative marker.

2.3. The comitative/reciprocal morpheme

The morpheme na is found in many Bantu languages, with different meanings and functions and different structural positions as well, a preprefix, a prefix, a free morpheme a suffix and a postsuffix. As a free morpheme it acts as a preposition, a conjunction or a verb. As as preprefix and a prefix, it acts as a tense marker and as a suffix, a derivational morpheme with different functions and as an inflectional suffix, an associative, a reciprocal or comitative.

Kinyarwanda.

1. Kabano na Kagabo 'Kabano and Kagabo'
Abáana barageenda na biísi. 'The children will be leaving by bus.'

When the morpheme na has a manner function it can occur as free morpheme before the head noun or as a suffix to the verb.

2. Umwáana akora n'íngoga.'The child works with speed'
Umwáana akorana ingoga. 'The child works with speed'

When it means 'also' it is either realized as a free morpheme before the conjoined noun or phrase or as a prefix which occurs between the tense marker and the object pronoun as seen below.

3. Abáana ba-shobor-a nó ku-ta-záa-suur-a ababyéeyi.
children they-may-asp also to-fut-visit-asp parents
'They children may also not visit parents.'
Abáana ba-shobor-a ku-ta-záa-na-suur-a ababyéeyi.
children they-may-asp to-neg-fut-also-visita-asp parents
'The children may also not visit parents.'

This comitative/reciprocal meaning has also been lexicalized. It is found with them which have an intrincical reciprocal meaning.

4. gutóongana 'to quarrel', kurwáana 'to fight', gusáambana 'to commit adultery', kubúurana 'to fight in court', gukíirana 'to wrestle', ...

In Kiswahili -na is an independent verb which means 'to have' and in Setswana (Ceissels), it is used as an auxiliary and means also 'to have' or 'to be with'. and as in many Bantu languages, it occurs as prefix referring to the present tense. In Chichewa (Mchombo, 1993) it refers to the past tense.

In Kindendeule, it is a negative marker:

5. ne na-ku-hik-a
I neg-to-come-asp
'I am not coming.'

li-himba na-ku-lum-a ba-ndu
5-lion not-to-bite-asp 2-people
'The lion is not going to bite people.'

In Kifuliiru (Van Otterloo, 2001) -na- as a prefix is used as either a sequential tense marker or as in Kinyarwanda to mean 'also':

6. Tw-a-na-mal-a siku ny-ngi mu ma-libu tw-a-na-lindi hik-a i kaaya.
we-pst-seq-finish-fv days 10-days in 6-suffering we-pst-seq-finally arrive-fv 23 home
'We spent many days in suffering and finally made it home.'
U-bw-ato bw-ana-yingir-a mwa mw-iji halinde bw-ana-hambiri yulubir-a.
aug-14-boat 14-seq-enter-fv in.it 6-water until 14-seq-amost-fv sink-fv
'Water was entering the boat until it was on the point of sinking.'

In South Western Bantu languages, Gciriku, Luvale, Lukazi (Fleisch), the prefix -na- is a prefect marker.

2.4. The locative morpheme mu and ku

Another good example of grammaticalization in progress is the use the locative prepositions ku and mu in Kinyarwanda. They are also realized as kuri and muri, respectively if the head noun is preceded by a demonstrative or the head noun doesn't have a preprefix.

In Kinyarwanda, these prepositions precede their head nouns, but they also come ather these head nouns as case markers or as post suffixes to the verb.

1. gutá igitabo mu máazi 'to throw the book in the water'
to-throw book in water
gutá amáazi mó igitabo
to-throw water-in book
gutá mó amáazi igitabo.
to-throw-in water

kwaandika izína ku rupapuro.'to write a name on the paper'
to-write name on paper
kwaandika urupapuro hó izína.
to-write paper-on name
kwaandika hó urupapuro izína.
to-write-on paper name

As verb postsuffixes, they also behave as object pronouns and some of them have been lexicalized without having any semantic or grammatical function.

2. kw-aandik-a hó < kw-aandik-a ku rupapuro 'to write on the paper.'
'to-write-asp loc
'to write on it.'

gu-kór-a mó < gu-kór-a mu máazi 'to touch in the water.'
to-touch-asp loc
'to touch in it.'

gu-shyír-a hó < gu-shyír-a ku méezá 'to put on the table.'
to-put-asp-it
'to put on it'

Like in the case of the reciprocal/comitative morpheme, these locative prepositions have also been lexicalized and found as suffixes to verbs without any other meaning or function:

3. kubáhó 'to exist'
guhítamó 'to select/choose'
kwíirirwahó 'to survive the day'
kuramukahó 'to survive the night'
gusúbiramo 'to repeat'
gusígaho 'to stop'

In Lunda, the preposition ku which also appears as hu : is also realized as a verb suffix to indicate tense (Kawasha):

4. W-a-món-a-hu dehi mutúpa.
s/he-pst-see-fv-loc already lion
'S/he has ever seen a lion.'

A-aka-y-anga-hu dehi.
they-ftu-go-asp-loc already
'They will have already gone.'

Matewu w-a-shík-il-anga-hu dehi.
M. he-pst-arrive-rp-impf-loc already
'Matewu had already arrived.'

III. Conclusion

The study of the morpheme nga in different Bantu languages has shown this morpheme to be polyfunctional and to occupy different structural positions in the sentence and the verb architecture. The perennial linguistic question about homonymy and polysemy was raised again and the metonymic association between the different meanings and functions of this morpheme shows clearly that it is indeed polysemy which wins, that is it the same morpheme which has developed these different meanings and functions.
This phenomenon was shown not to be unique because there are other morphemes which exhibit the same behavior.

Bantu languages,since they are still iconic as far their morphology is concerned, they are a good interesting testing area as far as semiotics and grammaticalization are concerned. They show the genesis and dynamism of signs and structures, how they go from transparency to opacity or iconicity to symbolicity or how words change their categories.
Grammaticalization clearly predicts that content words, verbs and nouns become function words such as auxiliary verbs, prepositions, conjunctions, tense-aspect-modality markers.
Auxiliary verbs developed from regular verbs (see Heine, Kimenyi, Van Otterloo).
Kinyarwanda complementizers, subordinators, conjunctions come from full verbs also (Kimenyi, 1988) and this seems to be the case in other Bantu languages as well. The verb
-amba in Kiswahili is used as an function word in relative clause and also as a complementizer 'that'. It means 'to say' and is realized in other Bantu languages such as Kinyarwanda as ku-gamb-a. The verb kuti 'to say' has the same function as -amba in Swahili in many Bantu languages. In Kinyarwanda, it is used only to introduce a reported speech as in:

Abáana ba-ra-vuz-e ba-ti: Tu-ra-shoonj-e.
children they-t-say-fv they-say: we-t-be hungry-fv
'The children just said: we are tired'

The tense markers have been shown by many linguists to come from regular verbs also.For instance, the following Swahili morphemes, all come from recognizable verbs:
-li-'pst'<-li 'be', -ta- 'fut'< -taka- 'want', -na- 'pres'< '-na 'have'/'with', -nge- 'cond'< nga 'like'/'how', -ja- 'neg'<-ja 'come', -me- 'pref'<-mala 'finish' (Ashton 1944, Heine and Reh 1984, Nurse 1989, Schadeberg 1989.

Many prepositions in Bantu languages come from nouns which refer to body parts or landscape (Heine, Kimenyi ):
examples:

heejuru /ha-ijuru: place+sky/ 'on top': heejuru y'áaméezá 'on the top of the sky'
mu(n)sí /mu-isí: in+earth) 'under': mu(n)sí y'áaméezá 'under the table'
ndani /stomach-in/: inside (Swahili).

The study of "nga" indicates that it is still possible to reconstruct the full forms and meanings of the tense-aspect-modality morphemes of the whole Bantu linguistic group.

In Peirce's semiotics, the phonetic and semantic change is always expected. Iconic signs and structures are expected to become symbolic with meaning change and phonetic shrinking, thus moving from transparency to opacity. Content words since they are semantically loaded have a larger phonetic shape whereas function words become smaller in shape.Desemanticization and polysemy go hand in hand.
The same morpheme occupying different positions in the same structure is a serious problem for a structuralist-generative theory. This phenomenon strongly argues for a theory which recognizes the dynamic nature of signs and structures and that therefore a panchronic approach is better suited to describe and explain linguistic phenomena. Both grammaticalization and Peircian Semiotics recognize this fact and can handle these "emerging structures" (Hopper).
Polysemy is also natural in cognitive linguistics. Polysemy and deiconization or symbolicity are part of the "minimalist" approach to language design. Languages tend to use a finite set of rules and structures but also , despite a large dictionary inventory, a minimum of words (as also shown by the use of metaphors) as well to create this dynamic "emerging grammar".

References:

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