how do I change the post title

Too hot and sticky to do any real work, and Chinese air conditioning is extremely milquetoast, so time for an a priori Thing. First, the inventory of Pre-Proto-Thing.

*p *t *tʃ *k *ʔ
*b *d *dʒ *g
*ᵐp *ⁿt *ⁿtʃ *ᵑk
*ᵐb *ⁿd *ⁿdʒ *ᵑg
*m *n *ŋ
*θ *s *x *h
*ð *z *ɣ *ɦ
*w *r *y
*l
*w̃ *ỹ

*i *ɯ *u
*e *ɤ *o
*a


Pre-Proto-Thing (let's say the root for 'speak' was *sat, with 'speech' being *sɯlat—so Pre-Proto-Sylatic) roots of the form C(R)VC. Words were generally up to three syllables long, as Pre-Proto-Sylatic allowed prefixes CV- infixes -VC- and suffixes -V(C) on roots. Thus:

*sat 'speak (singular object)'
*sotat 'speaker' (agentive)
*satVk 'speak (plural object)'
*sinat 'speak using' (instrumental applicative)

and so on and so forth.

Between Pre-Proto-Sylatic and Proto-Sylatic, a number of changes take place.

- Prenasalized stops and nasalized sonorants merge with their non-nasalized counterparts, becoming nasalization on a preceding vowel. Seven nasal vowels soon collapse to three— *ę *ǫ merge to *į *ų, *ɤ̃ becomes *ą, and *ɯ̃ merges with *ų if next to a labial and *į otherwise.

- *tʃ *dʒ become *ts *dz but change a following *ɯ *ɤ to /i e/ (this postdates the above change).

- Finally, the language develops sequisyllables. The root vowel remains stressed, and a preceding syllable developing from an infix or prefix becomes a sequisyllable. In sequisyllables any high vowel collapses to /ɯ/, and any non-high vowel collapses to /a/. However, the vowels spit out glides, so *C[i į] > Cyɯ, *C[u ų] > Cwɯ, and Ce Co > Cya Cwa. Nasalized vowels are oralized without a trace. Final syllables also become semi-sequisyllabalized insofar as their vowels undergo the same collapse (but without the glide development).

Thus, in Proto-Sylatic proper:

*p *t *ts *k *ʔ
*b *d *dz *g
*m *n *ŋ
*θ *s *x *h
*ð *z *ɣ *ɦ
*w *r *y
*l

*i *į *ɯ *u *ų
*e *ɤ *o
*a *ą


with a word structure (σ₁)σ₂(σ₃), where σ₁ is C(w j)[a ɯ] and σ₃ is [a ɯ]C.

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Proto-Sylatic can be described as generally isolating. There is a small amount of inflection: verbs with plural objects take the ending -ak, and pronouns show signs of an earlier accusative ending -ŋ. They also have object clitic forms on verbs with no final sequisyllable, preceded by -ɯ- (the plural -ak seems to be older and irregular). Nouns have no morphological plural (their plurality will be marked on the verb if they're objects, however).


nom acc clitic possessive
1sg *sap *sąp *=s *paŋ
2sg *dɤ *dɤŋ *=d *dɤŋ
3sg *ha *haŋ *=ʔ *haŋ
1pl *θaw *θoŋ *=t *θoŋ
2pl *ye *yeŋ *=y *yeŋ
3pl *ka *kaŋ *=k *kaŋ


Syntax

The syntax is strongly head-initial and VSO, but the clitic system suggests that this may have been a recent development, perhaps with an earlier VOS stage.

θaŋak-ak tsįg wa myo dzi
kill-pl man the cow PST
'The man killed (some) cows.'

za=s tsįg wa dzi
see=1sg man the PST
'The man saw me'.

Topics may be brought to the front with the marker ney.

myo ney θaŋak-ak tsįg wa dzi
cow TOP kill-pl man the PST
'As for cows, the man killed some.'

Adjectives are stative verbs:

myo wa lɤŋ
cow the big
'The cow is big.'

Both relative clauses and attributive adjectives are formed with the subordinator kya:

θaŋak-ak tsįg wa lɤŋ kya myo dzi
kill-PL man the big SUB cow PST
'The man killed some big cows'.

za θaŋak-ak myo dzi kya tsįg wa prɤj dzi
see kill-PL cow PST SUB man the fire PST
'The man who killed some cows saw fire.'

Negation is accomplished with the verb θe, which takes any object marking or clitics and changes the rest of the sentence to SVO:

θe myo wa θaŋak paŋ hų dzi
not cow the kill my father PST
'The cow didn't kill my father.'

θe=s zaza paŋ hų
not=me look my father
'My father isn't looking at me.'

Questions are formed with the sentence-initial (but non-syntax-changing) particle naʔ:

naʔ zaza=k dɤ myo wa
Q look you cow the
'Are you looking at the cows?'

Further aspects of syntax are difficult to reconstruct. It's known that aspectual and tense particles came sentence-finally, as we've seen with dzi. The clitic system in verbs is based only on a single descendant; there may have been other inflectional categories which were not preserved in any daughter.