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Japanese Language

Use when asked to write, translate into, or check text in Japanese (日本語) — the mixed kanji/hiragana/katakana writing system, the grammatically-encoded keigo honorific system, and subject-object-verb order with frequent subject omission — spoken mainly in Japan.

Japanese (日本語, Nihongo) is spoken mainly in Japan, with substantial communities of speakers elsewhere. It combines three writing systems in ordinary text, marks politeness and social relationship directly in verb grammar, and orders sentence elements very differently from English.

Writing system: three scripts used together

Real Japanese text mixes all three of the following in a single sentence — it is not a choice of one script over another the way Simplified vs. Traditional Chinese is:

  • Kanji (漢字) — Chinese-derived characters used for the core content words: most nouns, and the stems of verbs and adjectives.
  • Hiragana (ひらがな) — a syllabary used for grammatical elements (verb/adjective endings, particles) and for native words that either have no common kanji or are conventionally written in kana.
  • Katakana (カタカナ) — a syllabary used mainly for loanwords from languages other than Chinese, foreign names, onomatopoeia, and text needing visual emphasis (similar to italics in English).

A sentence like "私はコーヒーを飲みます" (I drink coffee) uses kanji (私, 飲) hiragana (は, を, み, ます) and katakana (コーヒー) all at once. Writing everything in one script, or replacing kanji with hiragana throughout, is not a neutral stylistic simplification — it reads as childish, or in some contexts as if the writer cannot use kanji.

Keigo: grammatically encoded honorifics

Japanese formality is not just word choice — it is built into verb conjugation itself through the keigo system, with several overlapping dimensions:

  • Teineigo (polite form) — the baseline polite register using -masu/-desu verb endings, appropriate for most interactions with people outside one's inner circle.
  • Sonkeigo (respectful language) — elevates the listener or a third person being discussed, used for superiors, customers, or people of higher status.
  • Kenjōgo (humble language) — lowers the speaker's own actions relative to the listener, often via entirely different verb forms (e.g. いたします instead of します for "to do").

Which register to use depends on the relative status and social distance between speaker, listener, and any third party mentioned, and it must generally stay consistent across a whole passage — mixing casual verb endings into an otherwise polite paragraph, or vice versa, reads as a clear error rather than a stylistic quirk.

Word order and subject omission

Japanese is subject-object-verb (SOV): the verb comes last, and particles (は, が, を, に, で, and others) mark each element's grammatical role rather than word order alone doing so. Subjects, objects, and even whole clauses are routinely omitted when clear from context — unlike English, which generally requires an explicit subject in every sentence. A sentence that literally translates as just "went" can be a complete, natural Japanese sentence when the speaker is already clear from context; forcing an explicit subject/pronoun into every sentence when translating into Japanese produces unnatural, overly explicit text.

Formal/written vs. casual/spoken register

Beyond keigo's status-marking, Japanese has a separate register axis between formal written Japanese (which favors -masu/-desu endings, fuller sentence structure, and more kanji) and casual spoken Japanese (plain-form verb endings, sentence-final particles like よ/ね/わ, and more contractions). This choice runs through an entire text, not just individual words — a novel's narration, a business email, and a text message between friends read as distinctly different registers from the first sentence.

Common pitfalls

  • Writing a sentence entirely in one script, or overusing hiragana where kanji is conventional, which reads as unnaturally simplified.
  • Mixing keigo levels inconsistently within one passage — starting polite and slipping into casual plain form, or the reverse.
  • Using sonkeigo (respectful) forms to describe one's own actions instead of kenjōgo (humble) forms — a common and noticeable error.
  • Inserting explicit subject pronouns (私, あなた) in every sentence when context already makes the subject clear, producing stilted text.
  • Treating katakana loanwords as freely interchangeable with their kanji/hiragana native-word equivalents — they often carry different nuance or register.

Learn more

View japanese-language/SKILL.md on GitHub