Proto-Simatsan

Proto-Simatsan is the first form of a conlang spoken by a fictional group of people on a hypothetically-existing isolated tropical island.

Phonology and Phonotactics
The syllable structure is (C)V, with stress falling on the antepenault by default. The only exception of where stress doesn't fall on the antepenault is when it falls on the penault, but only if the penault has a long vowel.

Writing System
The writing system would start as a logography being carved into trees with obsidian knives or flint. Because it would be easier to carve the glyphs in the direction of the grain, resulting in strong vertical lines being thicker than horizontal lines. And to allow usage for the full height of the trees, the writing direction would be top-to-bottom.

Later, the language would be written on palm leaves, the vein structure discouraging angular gestures and whatnot, leading to a more curvilinear form. And later on, the logography would adopt the rebus principle and become a logosyllabary.

Grammar and Syntax
Word order: SOV

Adjectives are evolved from nouns and come before the ones they modify. Adpositions are derived from verbs, and follow the nouns they modify, leading to them being known as postpositions. Possessors come before possessees. This language is mostly head-final as a result of all this.

Grammatical number:singular and plural.

The singular would be unmarked, with the plural getting a preceeding adjective, /ra/. Auxiliary verbs are a thing, and will come at the very end of the sentence.

In terms of valency, the passive and the causitive are used. The passive would evolve from the word for "take" and the causitive would evolve from the word for "cause".

Nouns
ālu: person

kīma: animal

tlete: rock

tamo: tree

kihu: place

tlipi: fire

hele: grass

potu: home

о̄mu: house

hlipa: fish

tsuli: water

tetsa: road/path

lamu: tiger

Verbs
pohlu: to see

kо̄: to sit

pao: to give

ua: to go

ahi: to finish

nо̄a: to take

kāni: to cause

tuke: to hunt

Pronouns
pē: I/me

hla: you(singular)

ne: he/she/it

si: we/us

tsо̄: you(plural)

wā: they/them

Adjectives
mā: big(evolved from "the big thing")

Adpositions
kо̄: at/in/on

Nouns
tamokihu: forest(tree+place)

tlipikihu: firepit(fire+place)

helekihu: field(grass+place)

potukihu: house(home+place)

Verbs
hlipatuke: fish-hunt(ing)/fish(ing)

tukālu: hunter

hlipatukālu: fisherman

tsulitetsa: river

lamutuke: tiger-hunt(ing)

Idioms
lamutuke(to hunt tigers): to persue a frivolus or lofty goal, typically to boost one's ego, which will probably fail

tili tekea rata ua(gone to fight without a spear): to make a mistake before a task has even begun

repikelo(to dip one's foot in): to try something new

isamu(to paddle): to be in the process of learning a topic

tsulitapu(to tread water): to be experienced in a topic, to understand well