The rule
To make a noun plural, say it twice, joined by a hyphen. Nothing is added, nothing changes inside the word.
| Singular | Plural | English |
|---|---|---|
| anak | anak-anak | children |
| ruma | ruma-ruma | houses |
| rafiki | rafiki-rafiki | friends |
| din | din-din | days |
That works on every noun in the language, with no exceptions, because there is nothing that could go wrong: no ending to choose, no sound to change, no list of irregulars.
After a number, the noun stays single
If the sentence already says how many, the noun is not doubled.
| tri anak | three children |
| du ruma | two houses |
| cok rafiki | many friends |
The number has done the work; repeating it would be saying the same thing twice. This is the same principle as tense: once the information is there, it is not restated. (Anak-anak on its own means “children, more than one, count unspecified”.)
Where plurals are not needed
The unmarked noun is neutral, not singular. Mi kan anak means “I see a child” or “I see children” — whichever the situation makes obvious. Doubling is used when the plural actually matters and nothing else in the sentence shows it.
Sources
Doubling a word to mean “more than one” is one of the most widespread devices on Earth:
| Family | Example |
|---|---|
| Austronesian | Indonesian/Malay anak-anak (children), rumah-rumah (houses); Tagalog |
| Sino-Tibetan | Chinese rén-rén 人人 (everyone), tiān-tiān 天天 (every day) |
| Japonic | Japanese hito-bito 人々 (people), yama-yama 山々 (mountains) |
| Dravidian | Tamil, Telugu — distributive and plural reduplication |
| Afro-Asiatic | Somali, Hausa — plural by partial reduplication |
| Turkic | Turkish keeps nouns single after a number (üç çocuk, never üç çocuklar) — the second half of this rule |
Keeping the noun single after a numeral is itself shared by Turkish, Hungarian, Persian, Chinese, Japanese, Korean and Indonesian.
Why this and not the alternatives
Why not a suffix (-s, -ler). A suffix is easy while it is regular, and in every natural language that has one it stops being regular: English child/children, Spanish lápiz/lápices, Arabic broken plurals. Doubling cannot drift because there is no form to drift.
Why not a particle (like suda for tense). A plural particle placed before the noun would behave exactly like an article, and design rule 3 says no articles. Placed after the noun it would be one more word to learn and one more position rule; doubling needs neither.
Why not “no plural at all” (the Chinese model). Tempting, and it is why the unmarked noun is neutral here. But learners coming from languages with obligatory plurals need some way to say “more than one” when it matters. Doubling gives them one without making it compulsory.
Candidates rejected, and why:
| Candidate | Source | Reason rejected |
|---|---|---|
| -s | English, Spanish, French, Portuguese | Indo-European only; breaks rule 4 for a feature this basic |
| -ler | Turkish | one family; and as a separate particle it has no meaning to a non-Turkish speaker |
| men | Chinese -men 们 | in the source it works only on people and pronouns — borrowing it as a general plural would misrepresent Chinese |
| tachi | Japanese -tachi たち | same problem: people only |
| duo (many) | Chinese duō 多 | introduces the vowel sequence uo, not attested in the language |
Open questions
Pronouns— settled: mi-mi, yu-yu, ta-ta are confirmed; see pronouns.md.- Whether doubling may also carry the distributive sense some source languages give it (din-din = “every day”), or stays strictly plural.