In the last post on this topic, I glossed over the development of the Modern Okinawan simple (imperfective) realis form from an earlier continuous realis form. This will be a short post simply describing what I think the series of phonological and morphological changes involved are.
For illustrative purposes, we’ll use the verb root √kak– ‘to write’. The original form would have been something like *kak-i+wor-um |write-INF+CONT-RLS|.
First, the evidence we have for the realis originally being *-um. In both Western and Eastern Old Japanese, we only find -u (or -i with r-irregular verbs) as what Vovin (2009: 595) calls the final predication form (what I call the realis form). However, the situation is different in the Ryūkyūan subgroup. In Okinawan, we find a number of forms ending in a nasal, as in the simple realis form, given in (1):
(1) kach-un |write-RLS| ‘[Someone] writes.’
The most crucial piece of evidence, however, is the realis form followed by the general question clitic =i. For instance:
(2) kach-um=i |write-RLS=GQ| ‘Does [someone] write?’
It appears that at some point in the history of Okinawan the distinction between syllable-final -m and -n was neutralized and we only find syllable-final -n. But in the form with the general question enclitic, there is resyllabification, and instead of being syllable-final, the underlying -m is now syllable-initial, and it is now licit for it to appear overtly as m. I will represent this underlying form as -uM.
The next point we need to explain is the palatalization of the verb root *√kak- with the realis suffix -un. There appears to be no overt synchronic motivation, but a diachronic explanation of a following infinitive form motivating the palatalization to *kat͡ɕ-i ( < *kakʲ-i. But -uM should not prompt the infinitive. The only reason we would expect the infinitive in this context is with an auxiliary verb. In Western Old Japanese, for instance, we find that nearly all of auxiliaries and some converbs following this pattern (such as the clause chaining converb -te, which always follows an infinitive), and even in Modern Japanese, we find compound verbs formed on this pattern (for instance, tob-i+kom-u |jump-INF+into-IPFV| ‘[Someone] jumps into [something]’).
Another neutralization involved the auxiliary verb wor- |CONT| (as a lexical verb ‘to exist’). This was caused by the addition of a pair of rules. The first mandated consonantal onsets to all morpheme-initial positions. For vowel-initial morphemes, this was satisfied by the addition of a glottal stop. Thus, PR *ame ‘rain’ (< PJ *Samay1 ‘rain’) became pre-Modern Okinawan *ʔame ‘id.’. Additionally, the initial consonant of wo, especially after raising to wu, became optional and could be replaced by a hiatus. wor- is unaccented, and thus high register in all Okinawan varieties, but although short vowels tend to be higher in pitch than their long counterparts (an apparent phonetic universal), it is not clear how pitch would have interacted here (as the pitch accent pattern of a main verb + auxiliary verb compound would likely be different than the root verb).
The most contentious point is the V2 elision, due to the fact that V2 elision is a typological rare phenomenon. V2 elision is a process where a sequence of two vowels, V1 and V2, results in the second vowel, V2, being deleted and the first vowel, V1, remaining. I propose that in this case, the motivation is the relatively higher sonority of *i versus *o (or, if it raises in the Northern Ryūkyūan chain shift before this point, *u, which is even less sonorous). In any case, both the infinitive *-i and the entirety of the auxiliary of *or- must both delete, as there is no residue of either in Modern Okinawan.
As I just mentioned, the initial vowel of the auxiliary *or- |CONT| then deletes, and creates an illegal consonant cluster (all non-geminate consonant clusters are illegal in Modern Okinawan), which then simplifies by deleting the second consonant.
We are then left with just the realis form -uM, which becomes the new simple (imperfective) form of the verb, and does double duty contrasting with both the perfective aspect (an expansion from its original continuous aspect meaning), and with various other mood markers (like the adnominal2 -uru and the tentative -ura)
kak-i+or-um (introduction of contrast between o with a non-glottal onset, (w)o, and with a glottal onset, ʔo; hiatus optionally replaces glide)
kak-i+or-uM (neutralization of syllable-final -n/-m contrast)
kakʲ-i+or-un (palatalization of k- due to following -i)
kakʲ-i+r-un (V2 elision of o)
kakʲ+r-un (deletion of i due to palatalization of kʲ-)
kakʲ+un (deletion of r due to illegal consonant cluster)
kakʲ-un (reanalysis of auxiliary as suffix)
kat͡ɕ-un (affrication of kʲ- to t͡ɕ-)
(1) The *S stands for some sort of fricative. In certain compounds, ‘rain’ shows up with an initial s-. For instance, WOJ pîsamë ‘hail’ (< pî ‘ice’ +samë ‘rain’). Vovin (2010: 109) speculates that this may be PJ *z or *h.
(2) I consider the adnominal form a mood marker due to its interaction with so-called focus particles. In addition to being used to form relative clauses, it is obligatory when the emphatic focus particle =du is used in a sentence, like how the realis mood is typically obligatory, or how the tentative mood is used when the general question particle is unraised. Compare (4a), (b), and (c):
(4a) sumuchi=∅ kach-un
‘[Someone] writes a book.’
(4b) sumuchi=du kach-uru
‘[Someone] writes a book‘
(4c) sumuchi=ga kach-ura
‘[Someone] writes a book?’
Vovin, Alexander. 2009. A Descriptive and Comparative Grammar of Western Old Japanese. Part Two: Adjectives, Verbs, Adverbs, Conjunctions, Particles, Postpositions. Folkestone: Global Oriental.
Vovin, Alexander. 2010. Koreo-Japonica: A Re-Evaluation of a Common Genetic Origin. Folkestone: Global Oriental.
∅ – null
– – morpheme boundary
+ – compound boundary
ACC – accusative case
ADN – adnominal mood marker
CONT – continuous aspect marker
EFP – emphatic focus particle
GQ – general question (yes/no-question) particle
INF – infitivie
IPFV – imperfective aspect marker
IQ – information question (wh-question) particle
RLS – realis mood marker
TENT – tentative mood marker