In English, "not" is a little word you drop into a sentence: I do *not go, **not expensive, **not a student. One word, three jobs, always separable. Japanese has no such word. *Negation is inflectional, not lexical — instead of adding a "not," the predicate itself changes shape. And crucially, how it changes depends on what kind of predicate you are negating. This page maps the whole territory before the following pages drill each piece; think of it as the table of contents for saying "not."
Three predicate types, three negative tracks
Japanese sentences end in one of three kinds of predicate — a verb, an い-adjective, or a noun / な-adjective (which predicates through the copula だ／です). Each negates its own way:
| Predicate type | Affirmative | Plain negative | Polite negative |
|---|---|---|---|
| verb | 食べる (eats) | 食べない | 食べません |
| い-adjective | 高い（たかい）(is expensive) | 高くない | 高くありません |
| noun + copula | 学生だ（がくせいだ）(is a student) | 学生じゃない | 学生ではありません |
| な-adjective | 静かだ（しずかだ）(is quiet) | 静かじゃない | 静かではありません |
私は肉を食べない。
watashi wa niku o tabenai
I don't eat meat.
この店はそんなに高くない。
kono mise wa sonna ni takaku nai
This shop isn't all that expensive.
あの人はもう学生じゃない。
ano hito wa mō gakusei ja nai
That person isn't a student anymore.
The single most important habit this whole group will build is: before you negate, ask what kind of predicate you have. Get that right and the correct track follows automatically. Get it wrong and you produce the two commonest beginner errors in the language — ×高いじゃない and ×食べるじゃない — which come straight from English, where one "not" fits everything.
There is no "not" — the predicate morphs
Look again at 食べる → 食べない. You did not insert a negating word next to the verb; you swapped the verb's tail. The negativity lives inside the inflected form. This is the mental shift English speakers must make: stop hunting for a word to place, and instead reshape the predicate.
- Verbs shift to a negative stem and add ない — 行く → 行かない (casual) / 行きません (polite). The mechanics live on plain 〜ない and polite 〜ません.
- い-adjectives replace their final い with くない — 高い → 高くない, 面白い → 面白くない. Never ×高いじゃない.
- Nouns and な-adjectives negate the copula: だ → じゃない / ではない. The full register ladder (じゃない → ではない → じゃありません → ではありません) is on the negative copula.
週末はどこにも行きません。
shūmatsu wa doko ni mo ikimasen
I'm not going anywhere this weekend.
この問題はそんなに難しくない。
kono mondai wa sonna ni muzukashiku nai
This problem isn't that hard.
The hidden unity: every negative ends in ない
Here is the elegant fact that ties the three tracks together. Look down the plain-negative column: 食べない, 高くない, 学生じゃない. They all end in ない. That is not a coincidence — the same ない is doing the negating in each, and that ない is itself a genuine い-adjective (originally the word for "non-existent"). Three tracks flow in; one shared ない flows out.
This matters enormously for everything downstream, because once you have any negative, all its further forms — past, te-form, adverbial, conditional — come from one place: い-adjective inflection. Watch the past tense fall out identically across all three tracks (drop い, add かった, exactly like 高い → 高かった):
| Non-past negative | Past negative |
|---|---|
| 食べない | 食べなかった |
| 高くない | 高くなかった |
| 学生じゃない | 学生じゃなかった |
昨日は忙しくて、何も食べなかった。
kinō wa isogashikute, nani mo tabenakatta
I was busy yesterday and didn't eat anything.
思ったより高くなかった。
omotta yori takaku nakatta
It wasn't as expensive as I'd thought.
Words that demand a negative: negative-polarity items
A whole set of common words are only grammatical with a negative predicate — they can never finish an affirmative sentence. English has a mild version of this ("I don't have any," "nothing happened"), but Japanese leans on it heavily:
- あまり…ない — not very / not much
- 全然（ぜんぜん）…ない — not at all
- めったに…ない — rarely
- 何も（なにも）…ない — nothing
- 誰も（だれも）…ない — no one
- まだ…ていない — not yet
その話は全然知らなかった。
sono hanashi wa zenzen shiranakatta
I had no idea about that at all.
昨日のパーティーには誰も来なかった。
kinō no pātī ni wa dare mo konakatta
Nobody came to the party yesterday.
If you start あまり… or 全然…, your ear should already expect a negative ending — あまり食べない, never ×あまり食べる. These pairings are covered as they come up, but noticing them now trains you to hear a negative coming.
The map of this group
Each following page drills one strand of the system:
- Plain 〜ない and polite 〜ません — the two registers of the verb negative, and how to build them across all verb classes.
- Conjugating 〜ない: past, te-form, adverbial — treating ない as an い-adjective to reach every other negative form.
- 〜ないでください: please don't — the negative request.
- 〜ないで vs 〜なくて — the two negative te-forms and when each is right.
- The negative copula じゃない / ではない — the noun / な-adjective track in full.
Common mistakes
❌ 私はテレビを見るじゃない。
Incorrect — じゃない negates nouns and な-adjectives, never verbs. Negate the verb itself: 見ない.
✅ 私はテレビを見ない。
watashi wa terebi o minai
I don't watch TV.
❌ このケーキは高いじゃない。
Incorrect — an い-adjective negates its own ending, not the copula. 高い → 高くない.
✅ このケーキは高くない。
kono kēki wa takaku nai
This cake isn't expensive.
❌ 彼はまだ学生くない。
Incorrect — 〜くない is only for い-adjectives. A noun negates the copula: 学生じゃない.
✅ 彼はまだ学生じゃない。
kare wa mada gakusei ja nai
He isn't a student yet.
❌ 昨日は何も食べないだった。
Incorrect — ない is an い-adjective, so its past is なかった; you never bolt だった onto it.
✅ 昨日は何も食べなかった。
kinō wa nani mo tabenakatta
I didn't eat anything yesterday.
Key takeaways
- Japanese has no word for "not." Negation is inflectional — the predicate changes shape.
- The shape depends on the predicate: verb → 〜ない／〜ません, い-adjective → 〜くない, noun / な-adjective → じゃない／ではない.
- Ask what kind of predicate is this? first — that one question prevents ×高いじゃない and ×食べるじゃない.
- Every negative ends in ない, and that ない is an い-adjective — so all past, te, and adverbial negatives (なかった, なくて, なく) come from one rule.
- Some words (あまり, 全然, 誰も, 何も) require a negative to complete them.
Now practice Japanese
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Start learning Japanese→Related Topics
- Plain 〜ない and Polite 〜ませんN5 — The two everyday verb negatives — casual 〜ない and polite 〜ません — as one meaning at two politeness levels, plus how to build each across godan, ichidan, and the irregulars.
- Conjugating 〜ない: Past, te-form, AdverbialN4 — Once a verb is negated with ない, that ない inflects exactly like an い-adjective — so past (なかった), te-form (なくて), adverbial (なく), and conditional (なければ) all fall out of one rule you already know.
- 〜ない Inflects Like an i-AdjectiveN4 — The structural key to every negative form — 〜ない is a genuine い-adjective, so its past is なかった, its te-form なくて, and it never takes だった.
- 〜ないで vs 〜なくて: The Two Negative te-formsN4 — Both translate as English 'not …-ing,' but Japanese splits them by what follows — 〜ないで leads into a chosen action ('without / instead / don't'), 〜なくて leads into an involuntary result or feeling ('because not').
- Negative: じゃない / ではないN5 — The negative copula on a register ladder — casual じゃない, written ではない, polite じゃありません / ではありません — plus why na-adjectives negate the same way but i-adjectives never do (高くない, never ×高いじゃない).