Localize Et

Estonian Translation Rules (et / eesti keel)

Distilled from the production translation prompt. Follow these rules verbatim — they are model-agnostic and produce consistent native-quality Estonian output.

Mindset

> Sa oled äärmiselt nõudlik eesti keele kirjanik, kes vihkab ebaloomulikke eestikeelseid väljendeid, nagu inglise keelest otseseid tõlkeid või kohmakaid sõnastusi.

Reject literal English calques and verbed anglicisms (klikima, downloadima). Estonian is a digital society — modern tech terminology is welcome, but native compound nouns are preferred over English borrowings.

Pre-Translation Setup

Lock in before translating:

1. Formality (sina vs Teie) — Default to sina (informal) for modern software. Teie is acceptable but reads stiff in most consumer/B2B UI. NEVER mix within a file.
2. 14 grammatical cases — Estonian has no prepositions; meaning is carried by case suffixes. Get the case wrong and the meaning shifts entirely.
3. No grammatical gender — ta = he / she / it. Adjectives agree in CASE and NUMBER only.
4. Partitive singular with numbers 2+ — UNIQUE to Estonian/Finnish. viis faili (singular!) NOT viis failid.
5. Placeholders — Preserve {variables} and ICU plural syntax exactly.

Register Auto-Detection (run after Pre-Translation Setup, before translating)

If the user has NOT specified sina or Teie, infer from source text register. Match output to source — formal source → Teie; informal source → sina. Estonian calibration is UNIQUE: even moderately formal source defaults to sina in modern software UI; Teie reads as stiff or old-fashioned in most contexts.

Formal source signals → output Teie / teie / Teid

• Hedging / polite modals: "please", "kindly", "we recommend", "we kindly request", "could you"
• Passive / impersonal constructions: "users are advised", "it is recommended", "applicants must"
• No contractions: "do not", "cannot", "we will"
• Domain vocabulary: legal, financial, healthcare, regulatory, government, banking, insurance, formal contracts
• Third-person / distance: "the user must", "customers should"
• Long sentences, formal connectors
• Brand voice: bank, government, legal tech, insurance, healthcare formal correspondence
• No exclamations or emojis

Informal source signals → output sina / sa / sinu / su (modern Estonian default)

• ANY of: contractions, casual greetings, emoji, exclamations, slang, consumer-app voice
• Lifestyle, gaming, social, e-commerce, productivity apps — all default to sina
• Marketing copy, newsletters, mobile UI — sina is the modern norm

Mixed / ambiguous source → default to SINA

This is OPPOSITE of most other languages (where formal is the safe default). In Estonian:

• Modern software UI: sina almost always.
• Teie reads stiff and may signal "outdated/government/elderly target".
• Only escalate to Teie if source is explicitly legal/banking/government, OR the user requests it.

Explicit user override

If the user says "use Teie" / "use formal" / "make it casual", their instruction wins.

Worked examples

| Source | Detected | Estonian output | |----------------|----------|------------------| | "Please review the terms of service before proceeding." | formal | Palun tutvuge teenusetingimustega enne jätkamist. | | "Hey! Tap here to get started — it's super quick 🚀" | informal | Tere! Puuduta siia, et alustada — see on imekiire 🚀 | | "Submit your application by the deadline." | formal | Esitage oma avaldus enne tähtaega. | | "Don't forget to save your work!" | informal | Ära unusta oma tööd salvestada! |

After detection: keep the chosen form consistent. NEVER mix sina/Teie across pronouns, possessives, OR imperatives.

⚠️ Critical Rules — Estonian Has Three Highly Distinctive Patterns

These three are the most common sources of unnatural output. They have no analogue in English/Romance/Germanic languages, so the model gets them wrong by default.

A. Numbers 2+ take partitive SINGULAR (severity 2.0)

| Wrong (English-style plural) | Correct (partitive singular) | |------------------------------|------------------------------| | viis failid | viis faili | | kolm kasutajad | kolm kasutajat | | kakskümmend failid | kakskümmend faili | | sada krediidid | sada krediiti |

Rule: only 1 takes nominative singular (üks fail). Every other number, including 0, takes partitive singular. This applies recursively in ICU plurals (see below).

B. ICU plural other = partitive singular (CRITICAL)

{count, plural, one {# fail} other {# faili}}
{count, plural, one {# krediit} other {# krediiti}}
{count, plural, one {# kasutaja} other {# kasutajat}}

| Wrong | Correct | |-------|---------| | other {# failid} | other {# faili} (partitive singular, not plural) | | other {# krediite} | other {# krediiti} |

The other branch is the partitive SINGULAR form. Common pitfall: most translators reach for the partitive plural by analogy with English/Spanish/etc.

C. Verb-governed case (severity 2.0)

Each Estonian verb dictates which case its object/complement takes. There's no general rule — these must be memorized.

| Verb | Governs | Example | Wrong (alt case) | |------|---------|---------|------------------| | aitama (help) | partitive | aitama kasutajat | aitama kasutajale | | sõltuma (depend on) | elative | sõltuma seadetest | sõltuma seadetel | | huvituma (be interested in) | elative | huvituma projektist | huvituma projekti | | otsima (search for) | partitive | otsima faili | (genitive form looks identical for fail) | | uskuma (believe) | partitive | uskuma teda | uskuma temale | | meeldima (please / X likes Y) | adessive subj. + nominative obj. | mulle meeldib see | minule meeldib seda | | vajama (need) | partitive | vajame faili | vajame failile | | ootama (wait for) | partitive | ootame teie vastust | ootame teie vastusele |

If the source uses an English verb that maps to one of these, double-check the case.

The 14 Cases — Full Reference

| # | Case | Question | Singular example (fail) | When to use | |---|------|----------|---------------------------|-------------| | 1 | Nominative | kes? mis? | fail | Subject of sentence | | 2 | Genitive | kelle? mille? | faili | Possession; motion direction (often) | | 3 | Partitive | keda? mida? | faili | Partial object; with numbers 2+; with certain verbs | | 4 | Illative | kuhu? | faili / failisse | Motion INTO | | 5 | Inessive | kus? | failis | Location IN | | 6 | Elative | kust? | failist | Motion FROM inside | | 7 | Allative | kellele? | failile | Motion ONTO; recipient | | 8 | Adessive | kellel? | failil | Location ON | | 9 | Ablative | kellelt? | faililt | Motion FROM surface | | 10 | Translative | kelleks? | failiks | Becoming; transformation | | 11 | Terminative | kelleni? | failini | UP TO (limit) | | 12 | Essive | kellena? | failina | AS (role) | | 13 | Abessive | kelleta? | failita | WITHOUT | | 14 | Comitative | kellega? | failiga | WITH (accompaniment / instrument) |

English preposition → Estonian case quick map:

| English | Case | Example | |---------|------|---------| | in the file | inessive | failis | | into the file | illative | faili (or failisse) | | from inside the file | elative | failist | | on the file | adessive | failil | | onto the file | allative | failile | | from the surface of the file | ablative | faililt | | with the file | comitative | failiga | | without the file | abessive | failita | | up to the file | terminative | failini | | as a file | essive | failina | | (becoming) a file | translative | failiks |

Common case errors (severity 2.0)

| Wrong | Correct | Why | |-------|---------|-----| | failis (for motion into) | faili | illative for "into" | | süsteemist (for location in) | süsteemis | inessive for "in" | | kasutaja (when partial object) | kasutajat | partitive for partial objects | | failes | failis | wrong case form |

Adjective agreement in case + number

Adjectives must agree with the noun in CASE and NUMBER. No gender to worry about.

| Wrong | Correct | |-------|---------| | uus faile (partitive plural) | uusi faile | | uue failid (nominative plural) | uued failid | | suur kasutajat | suurt kasutajat (partitive both) |

Formality — sina vs Teie

| Form | Pronoun | Possessive | Example | |------|---------|------------|---------| | Informal (sina) | sina / sa | sinu / su | Sa saad oma faili salvestada. | | Formal (Teie) | Teie / Te | Teie | Te saate oma faili salvestada. |

• Default to sina for modern software UI. Teie is for very formal/older contexts.
• NEVER mix pronouns, possessives, and imperatives within one file.
• Teie is capitalized when used as the formal address (Te / Teie / Teid); te / teie lowercase = "you all" (plural informal — rare in software UI).

Imperative endings:

• Informal sina: base form — Salvesta, Logi sisse, Vali kõik.
• Formal Teie: -ge / -te — Salvestage, Logige sisse, Valige kõik.

| Don't mix | Use | |-----------|-----| | Teie fail on salvestatud. Salvesta uuesti? | Teie fail on salvestatud. Salvestage uuesti? (formal) OR Sinu fail on salvestatud. Salvesta uuesti? (informal) | | Laadige üles + Sirvi faile | Laadige üles + Sirvige faile (both formal) |

Negation — invariant ei + same stem for all persons

| Wrong (conjugated after ei) | Correct (invariant stem) | |-----------------------------|--------------------------| | mina ei salvestan | mina ei salvesta | | meie ei salvestame | meie ei salvesta | | nad ei salvestavad | nad ei salvesta |

ei does the negation; the verb following is always the bare negative stem (looks like the present-tense ta form without ending).

Word Order

• Default: SVO — Kasutaja salvestab faili.
• V2 tendency when an adverb is fronted — the verb stays in the 2nd position:

| Wrong | Correct | |-------|---------| | Täna kasutaja salvestab faili | Täna salvestab kasutaja faili | | Pärast seda süsteem käivitub | Pärast seda käivitub süsteem |

Compound Words — Estonian Writes Them TOGETHER

Estonian aggressively compounds nouns. Hyphens are wrong except for abbreviations.

| Wrong (hyphenated like English) | Correct (one word) | |---------------------------------|---------------------| | faili-süsteem | failisüsteem | | andme-baas | andmebaas | | kasutaja-sõbralik | kasutajasõbralik | | pilve-põhine | pilvepõhine | | veebi-leht | veebileht |

Exception — abbreviations DO take a hyphen: XML-fail, e-post, IT-osakond.

Infinitives — Da vs Ma

Estonian has two infinitive forms; each verb selects the right one based on context.

| Trigger | Infinitive form | Example | |---------|-----------------|---------| | tahan, soovin, suudan, võin, oskan | -da | Tahan salvestada | | hakkan, lähen, pean, jään | -ma | Hakkan salvestama, Lähen ostma |

| Wrong | Correct | |-------|---------| | Tahan salvestama | Tahan salvestada | | Hakkan salvestada | Hakkan salvestama |

Consonant Gradation (severity 1.5)

Strong/weak alternation across cases:

| Strong | Weak | |--------|------| | pp → p | kapp → kapi | | tt → t | kott → koti | | kk → k | pakk → paki | | p → v | leib → leiva | | k → g / ∅ | leping → lepingu |

These shifts happen during inflection — important when generating case forms.

Punctuation and Typography

| Item | Estonian | |------|----------| | Decimal separator | , (comma) | | Thousands separator | (space) | | Example number | 1 234,56 | | Currency | 99,99 € (symbol AFTER, with NBSP space) — Estonia is in the Eurozone | | Date | 15.01.2024 (DD.MM.YYYY) or 15. jaanuar 2024 (lowercase months) | | Time | 14:30 or kell 14:30 (24-hour) | | Quotation marks | „..." (German-style low-9 open + high-6 close), NOT English "..." | | Ellipsis | … single character (NOT three periods) | | Ampersand | ja (NOT &, except in brand names) | | Space before unit symbol | yes (NBSP preferred): 10 MB, 99,9 % |

| Wrong | Correct | |-------|---------| | 1,234.56 € | 1 234,56 € | | "Estonian quotes" | „Estonian quotes" | | 01/15/2024 | 15.01.2024 |

Comma Rules (Estonian is comma-heavy)

| Before | Comma? | |--------|--------| | või / ja / ning (or / and) | No comma | | et / kui / sest / mis / kes / kuna (subordinating: that/if/because/which/who/since) | Comma always required | | aga / kuid / ent (but) | Comma required |

| Wrong | Correct | |-------|---------| | Näen et fail on avatud | Näen, et fail on avatud | | Lohistage siia, või klõpsake | Lohistage siia või klõpsake | | See on lihtne aga tõhus | See on lihtne, aga tõhus |

Preferred Terms (UI / SaaS vocabulary)

| English | Preferred Estonian | Avoid | |---------|--------------------|-------| | save | salvestama / button: Salvesta | — | | settings | seaded | sätted | | select | valima / Vali | — | | upload | üles laadima | uploadima | | download | alla laadima | downloadima | | log in | sisse logima / Logi sisse | — | | log out | välja logima / Logi välja | — | | update | uuendama | updateima | | cancel | tühistama / Tühista / Loobu | — | | delete | kustutama / Kustuta | deleteima | | search | otsima / Otsi | — | | file | fail (accepted loanword, invariable concept; takes Estonian case suffixes) | — | | folder | kaust | — | | email | e-post (e-kiri for the message) | email | | browser | veebilehitseja | brauser | | click | klõpsama | klikima | | dashboard | töölaud / juhtpaneel | — | | notifications | teavitused | notifikatsioonid | | native support | sisseehitatud tugi | loomulik tugi | | login credentials | sisselogimisandmed | konto mandaadid | | account | konto | — | | user | kasutaja | — | | Settings | seaded | sätted (older; both used but seaded more current) | | Profile | profiil | — | | Account | konto | — | | Sign up / register | registreeruma / loo konto | signupima | | Subscribe | tellima / tellida | subscribima | | Unsubscribe | tellimusest loobuma | — | | Submit | esita (button) / esitama | — | | Apply | rakenda (e.g., apply filter) / taotle (apply for something) | — | | Filter | filter / filtreerima | — | | Sort | sorteerima / järjesta | — | | Refresh | värskenda / uuenda | refreshima | | Copy | kopeeri / kopeerima | — | | Paste | kleebi / kleepima | — | | Cut | lõika / lõikama | — | | Undo | võta tagasi | undoma | | Redo | tee uuesti | redoma | | Confirm | kinnita / kinnitama | — | | Continue | jätka / jätkama | — | | Back | tagasi | — | | Next | edasi | — | | Skip | jäta vahele | skipima | | Share | jaga / jagama | sharima | | Help | abi | — | | Welcome | tere tulemast / tervitame | — | | Success | õnnestumine / õnnestus | — | | Error | viga | — | | Warning | hoiatus | — | | Loading | laadimine | — | | Saving | salvestamine | — | | Required | nõutav / kohustuslik | — | | Optional | valikuline | — | | Free / no cost | tasuta | — | | Paid | tasuline | — | | Premium | tasuline / premium | — | | Trial | prooviperiood | — | | Subscription | tellimus / tellimine | — | | Payment | makse / maksmine | — | | Invoice | arve | — | | Coupon | kupong / sooduskood | — | | Discount | allahindlus / soodustus | — |

Anglicism Verbs — Estonian Prefers Native

| Anglicism (avoid) | Native Estonian | |-------------------|------------------| | klikima | klõpsama | | downloadima | alla laadima | | uploadima | üles laadima | | deleteima | kustutama | | editima | muutma / redigeerima (loan but accepted) | | checkima | kontrollima |

Software Terminology

| English | Wrong | Correct | |---------|-------|---------

…

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: i18n-agent
• Source: i18n-agent/i18nstack
• License: MIT
• Homepage: https://i18nagent.ai

Install and usage instructions live in the source repository linked above.