Revisiting Basaa verbal derivation

Basaa, a Narrow Bantu language (A43) spoken in Cameroon in Central Africa holds a serious record of descriptive works in phonology, morphology, and syntax. Verb morphology has been studied in detail by Bitjaa Kody (1990), Dimmendaal (1988), and Hyman (2003), among others. The present paper focuses on verb derivation in Baasa, and raises two main issues: (i) the paradigm of expansions that are recurrent in the language, and (ii) extensions which suggest the existence of additional suffixes to what is already reported. Further extensions include the perfective, the associative, and the tentive. This paper concludes with an attempt to reconstruct Basaa extensions, mirroring Schadeberg’s (2003) Proto-Bantu propositions.

Basaa verb stems, as in many other Bantu languages, are a combination of the lexical root and one or two extensions. The structure of the verbal stem is thus: [RADICAL -(EXPANSION) -EXTENSIVE SUFFIX]. The final vowel has dropped out in most words in this language. Two aspects of Baasa verb morphology are studied here: morphological expansion and extensions.
The structure of the paper is as follows: in section 2, an overview of Baasa phonology is presented. Section 3 is devoted to morphological expansion, and section 4 to extensions. 1

Overview of phonology
Basaa phonology is complex enough, with several rules which take the verb stems some time to respect cyclicity given a sound internal hierarchy, without neglecting the templatic and largely concatenative nature of the morphology (Hyman 2000(Hyman , 2007. The following rules and processes have been accounted for in Basaa: Vowel Height Harmony (section 2.1), toneless suffixes (section 2.2), syncope (section 2.3), and phonotactics (section 2.4).

Vowel Height Harmony
This process appears only in verbal forms in the context of extension. As Schmidt (1994), followed by Mutaka and Bitjaa Kody (2000), and Sandy (2012) for Abo (A42), point out, Vowel Height Harmony (hereafter VHH) is a process by which the vowel of the verbal stem changes its aperture to a higher level, triggered by the extensive suffix that is added to it. It is important to note that not all the extensions are involved in this process.

Toneless suffixes
Apart from the stative suffix, which bears a H(igh) /-í/, all the remaining suffixes are toneless. They connect in three phases to the verbal root: i. They connect to the root and take a default L(ow); ii.
High tone spreading (HTS) when the root is H; iii.
HTS is blocked when as a result of derivation; there are then two consonants in a row following the root. (

Syncope
Work by Hyman (2000) reveals an active process taking place in Basaa, by which the second vowel in a (C)VCVCV sequence is deleted. Due to the vowel deletion process (V.C1V.C2V → VC1.C2V), two consonants become adjacent across syllable boundaries.

Phonotactics
When the habitual suffix /-a/ is added to a CVC root, syllabification into a CV.CV structure takes place. Basaa does not admit vowel clusters such as diphthongs. The language tolerates long vowels, but not two different vowels in a row. One strategy to repair ill-formed sequences is to introduce glides.

Formal expansion
In some cases, expansions may be identical to extensive suffixes, but the difference lies in the fact that the preceding syllable either has no lexical meaning or has lost it. This phenomenon is referred to in the literature as a "cranberry morpheme". Basaa displays four different expansions: #ra, #lɛ, #la, and #rɛ.
(5) Expansion with #ra hòɣ#rà 'to become muddled' ɲàɣ#rà 'to go bad' tíβ#rà 'to soak sth.' kwàɣrà 'to scrawl' júβ#rà 'to lose one's head' tɛɣ#rà 'to have the giggles' When drawing a semantic generalisation of the stems presented above, one can see the general theme of unsteadiness. These stems are all action predicates.
(7) Expansion with #la sàmblà 'to hug' pàβlà 'to hurry' pùβlà 'to hurry' sɛhlà 'to tremble' No semantic generalisation can be made of the stems presented in (7), as with the case of expansions with #lɛ.

Applicative
The applicative extension involves the action of being applied on behalf of, towards, or with regard to some object (Lodhi 2002). In the perspective of semantic roles, applicative verbs are expected to play the roles of beneficiary, place, time, cause, reason, and instrument.

Beneficiary
The beneficiary role is the most productive. The forms of the beneficiary are the following, depending on the form of the root: From the stems presented in (9) above, it is evident that all are monosyllabic, and VHH applies as a rule. But there is an exception with two verbs, presented in (10), that do not apply VHH per se. There is no phonological explanation for the behaviour of these vowels.
(10) kɛ̀ 'to go' kìl *kèl ɲɛ̀ 'to defecate' ɲìl *ɲèl 2 What is reported as imperfective (with the /-Vχ/ suffix) in previous works on the language will not be considered as an extension in this work, since this imperfective is inflectional. Examples are: (i) m-à:ŋgɛ́ à ɣá-kɛ-n-ɛχ á ɓɔĺ 1-child SM FUT2-go-IMP SM arrive 'After a long walk, the child will reach his destination.' PST1-finish-IMP NEG eat 'She has not yet finished eating.' The case is different when we move to disyllabic stems, where the suffix form is /-nɛ/ for open final syllables.

Place, time, cause, and reason
The applicative stems in the categories of place, time, cause, and reason behave phonologically like the beneficiary that we have seen above. The table presented in section 4.1.1, repeated here, is applicable to these stems. ǹ-sómb-ól βì-támb í ɓòm 3SG PST1-buy.APPL 8-shoe LOC 7.market 'She bought the shoes at the market.' sŭɣlù ì óŋ.nɛ́ lí-!kándá 9.school SM build.APPL 5-crossroads 'The school is located at the crossroads.'

Applicative as instrument
There are two forms to express the instrumental meaning of the applicative, namely /-na/ and /-Vl/. Unlike the other applicative structures specified above, the instrumental suffix /-na/ does not absolutely require the verb root to be disyllabic and end in /-a/. There is no phonological context to sketch the distribution of one form or the other.

Causative
This extension expresses "cause to do" or "cause to be" (Lodhi 2002). In Basaa, there are two ways to express the causative: direct causative, on the one hand, is when the agent acts directly on the patient and obtains a change over his/her being or doing; indirect causative, on the other hand, is when the agent gets the patient him-/herself to change his/her doing or being.
As concerns the direct causative, the form is /-Vs/ ~ /-Vh/. The vowel of the suffix is a copy of that of the root, which is under the VHH constraint. One also has to consider that, Additionally, it is important to note that the same verb can take the direct causative extension and the indirect causative suffix, resulting in different meanings. As an example, the verb [kɔǹ] 'to be sick' can refer in the direct causative to someone making another sick by doing something to the latter, like feeding or beating. Likewise, the indirect causative meaning denotes someone getting sick but not from the direct action of another.

Reflexive
The reflexive extension, which is highly productive in Basaa, entails three different nuances, presented as follows: As we can see from the data presented in above (24), the bilabial implosive /ɓ/ changes to the fricative /β/ when immediately following a vowel. It may happen sometimes that the same verb gathers both categories of reflexive, resulting in two different meanings. That is the case with tèŋ 'to attach / to tie', which can be derived into tèŋ-èɸ or tèŋ-ɓà.

Passive
The passive form, in its cross-language definition, involves an agent acting upon a subject. That is, the agent in the subject position and the patient/theme in the object position exchange their positions. Basaa displays two suffixes for the passive, namely /-a / (VHH), presented in (27b)

Positional (stative)
The positional or stative extension (Posit) implies that the subject is, at that moment, tied with a certain position or posture, and that position is likely to be durational (Lodhi 2002). This extension concerns only positional verbs. The suffix for the positional is /-í/ (VHH). VHH here is not automatic and does not concern disyllabic roots. When the verb root ends with an open syllable, there is an epenthetic /-l-/ that prevents two vowels becoming adjacent.

Habitual
The habitual extension demonstrates a tendency or practice that is settled or regular, by which someone is recognised (Lodhi 2002). The meaning is something like "she used to …". Verbs with the habitual extension can be transitivized or not. The form to mark habitual is /-a/, or /-na/ for vowel-final roots. In the case of long verb roots like CV:CV or CVCCV, the /-a/ of the suffix overrides the final vowel of the root.

Reversive
The reversive extension is meant to reverse the meaning of the root onto its semantic opposite. This extension is not highly productive and it gives way to transitive stems. The form is /-Vl/ (VHH), the same as that of the applicative. The vowel of the suffix will be a copy of that of the root, provided that it has undergone VHH.

Associative
This form indicates that the action is reciprocated or done "to one another". This extension, also referred to as the "reciprocal" (Ashton 1944), implies a plural subject (as from two subjects). The form that marks the associative is the suffix /-na/. When we have a long verb root like CV:CV or VCCV, the /-a/ of the suffix overrides the final vowel of the verbal stem.
In (35)  It is important to note that, along with the associative meaning "[verb] to one another", there is another sense of reciprocity among or between entities. The idea here is that of sharing.

Concomitant/contemporaneous
The concomitant extension is highly productive in Basaa and involves the action being predicated by the verb and occurring at the same time as a similar event by another agent, e.g., "the train arrives at the same time as the bus". The form of the concomitant is the post-radical suffix /-ha/ (VHH)the same reflex as for the indirect causative. As with the associative, the concomitant/contemporaneous extension is only relevant when the subject is plural. Since the /-ha/ cognate is also used for the causative, a singular subject will automatically attract a causative meaning.

Tentive
The tentive extension has not been accounted for in previous work on Basaa. The tentive (Schadeberg 2003), also referred to as the "contactive" (Meeussen 1967), involves the verbal stem containing semantic elements denoting actively making contact. In Basaa, there are two types of contact expressed through morphological means: psychological contact and physical contact. The form for psychological contact is /-ra/, while the form for physical contact is /-ɓɛ/. The second category of stems refers to physical contact, implying geographical proximity between two entities. Some of the verbs are transitive correlates of the reversive category, which is intransitive. The distinguishing trait of this extension is that the meaning denotes contact. 'to cradle' só:-βɛ̀ 'to get stuck in mud' kɔɸ 'to hitch sth. to' kɔ:-βɛ̀ 'to get stuck on'

Antipassive
In this section, I explore some data which show that the antipassive extension is at play in Baasa. According to Dixon (1994: 146), cited in Bostoen, Dom and Segerer (2015), a voice construction must meet the following four conditions to be considered antipassive: (i) It must be a detransitivized construction; (ii) The subject of the antipassive must correspond to the subject of the underlying active clause; (iii) The object of the base verb must either fulfil an oblique function, being treated as a non-core argument, or be omitted; (iv) There must be some overt formal marking, signalling an antipassive derivation.
In Basaa, the antipassive is expressed by the morphemes /-nà/ and /-à/, and this is evident with only two verbs, namely tɛ́hɛ̂ 'to see' and nùn 'to look'. c.
m-à:ŋgɛ́ à ń-nùn-à 1-child SM PR-look-ANTIPASS 'The child can look.' From the example above, we can see that tɛ́h-nà in (42a) expresses an associative meaningthe children looked at and saw each other. However, in (42b), the reading is not the same. Used in the singular, the idea of "having the capacity to see" is expressed, not the associative. Used in the plural, the sentence is ambiguous, as it can have both an associative and antipassive meaning. The case is almost similar with (42c), where the sentence expresses the idea of "having one's eyes open".

Summary and discussion
To sum up, the various extensions are presented in the following table: Extension Form Productivity Transitivity?