English says "Don't!" — a single curt word that cancels an action. Japanese has an equally short device: take the plain dictionary form of a verb and bolt な onto the end. 行く ("go") becomes 行くな ("don't go"); 見る ("look") becomes 見るな ("don't look"). This is the prohibitive form (禁止形, きんしけい), the exact negative mirror of the plain imperative. It is blunt, forceful, and — like the plain imperative — something you use in anger, in emergencies, or from a clear position of authority. This page shows how it is built, how harsh it really is, and how to keep it apart from a look-alike な that means almost the opposite.
The form: dictionary form + な
There is only one rule, and it is refreshingly regular: attach な to the plain dictionary form of any verb, regardless of class. Nothing changes about the verb itself.
| Verb | Class | Prohibitive | Meaning |
|---|---|---|---|
| 行く | godan | 行くな | don't go |
| 触る | godan | 触るな | don't touch |
| 見る | ichidan | 見るな | don't look |
| 食べる | ichidan | 食べるな | don't eat |
| する | irregular | するな | don't do |
| 来る | irregular | 来るな (くるな) | don't come |
Because it attaches to the unchanged dictionary form, the prohibitive is the single easiest verb form in Japanese to build — there are no sound changes, no stems, no exceptions.
危ない、触るな！
abunai, sawaru na
It's dangerous — don't touch (it)!
ここに入るな。
koko ni hairu na
Don't come in here. / Keep out.
人に嘘をつくな。
hito ni uso o tsuku na
Don't lie to people.
How blunt it really is
The prohibitive is rough. It carries the same force as the plain imperative 行け／見ろ: it commands, it does not ask. In everyday life you hear it in a narrow band of situations:
- Danger and emergencies — 動くな！ ("Don't move!"), 見るな！ ("Don't look!")
- Warnings on signs — 芝生に入るな ("Keep off the grass"), where the sign shouts at everyone impersonally
- Sports, drill, and coaching — 諦めるな！ ("Don't give up!")
- Close male peer speech and rough emotion — a heated argument, an older brother snapping at a younger one
Used at anyone you owe respect to — a stranger, a customer, a superior — bare 〜な is offensive. It is also statistically male and forceful: women and polite speakers reach for the softer alternatives below. This is not a rule you can ignore, because the harshness is the meaning: choosing 泣くな over 泣かないで is choosing to sound curt.
泣くな。もう終わったことだろう。
naku na. mō owatta koto darō
Don't cry. It's over and done with, isn't it? (blunt, consoling-but-gruff)
まだ諦めるな、最後まで走れ！
mada akirameru na, saigo made hashire
Don't give up yet — run to the finish! (a coach shouting)
The trap: prohibitive 〜な vs encouraging 〜な
Here is where English speakers derail. There is a second な, and it means almost the opposite. It is a warm, gentle command — a clipped, casual reduction of 〜なさい: 食べなさい ("eat, please") shortens to 食べな ("go on, eat"). Parents use it with children; friends use it to nudge each other along. Where the prohibitive slams the door, this な holds it open.
The two look identical on the surface, but the form they attach to is the entire distinction:
- Prohibitive な follows the dictionary form: 食べるな = "don't eat."
- Encouraging な follows the masu-stem (the 連用形, the same stem you use for 〜ます): 食べな = "go ahead and eat."
For an ichidan verb like 食べる, the only difference between "don't eat" and "go on and eat" is the single kana る:
| Dictionary + な (prohibitive) | Masu-stem + な (encouraging) |
|---|---|
| 食べるな (don't eat) | 食べな (go on, eat) |
| 見るな (don't look) | 見な (go on, look) |
| 寝るな (don't sleep) | 寝な (go on, sleep) |
| するな (don't do it) | しな (go on, do it) |
| 来るな (don't come) | 来な (きな) (come on) |
For a godan verb the contrast is just as sharp — the vowel of the last syllable flips from -u to -i: 行くな ("don't go") versus 行きな ("go on, go").
疲れてるなら、早く寝な。
tsukareteru nara, hayaku ne na
If you're tired, go on and get to sleep. (gentle, from the masu-stem 寝)
まだ寝るな、宿題が残ってるだろう。
mada neru na, shukudai ga nokotteru darō
Don't go to sleep yet — you've still got homework, right? (blunt, from the dictionary form 寝る)
遠慮しないで、たくさん食べな。
enryo shinai de, takusan tabe na
Don't hold back — go on and eat lots. (a host urging a guest, warm)
Notice that last sentence uses 食べな, the warm masu-stem invitation; had it been the dictionary-form 食べるな, it would have flipped to a rude "don't eat." Master the attaching form and you never confuse them again.
A third な: the emotive particle
To round out the picture: there is yet another な, the sentence-final emotive/feeling な, which expresses reflection or fishes for light agreement — close to English "…, huh" or "…, isn't it." Crucially, this one typically attaches to an adjective or the copula, where there is no possible prohibitive reading, and it is often drawn out as なあ.
今日はいい天気だなあ。
kyō wa ii tenki da nā
Nice weather today, huh. (musing to oneself — emotive な)
この店、安いな。また来よう。
kono mise, yasui na. mata koyō
This place is cheap, huh. Let's come again. (emotive な on an adjective)
The rule of thumb: な after a dictionary-form verb reads as a prohibition (行くな = "don't go"); な after an い-adjective or だ is emotive (いいな = "how nice"). Intonation and context finish the job — the prohibitive is barked and falling; the emotive drifts and lengthens.
Softening the edge with よ
Adding the particle よ to a prohibitive can nudge it from a bark toward an insistent reminder among friends — 行くなよ ("don't you go now"), 忘れるなよ ("don't you forget"). It stays casual and still would not do for a superior, but it feels less like a shout and more like a nagging peer.
このこと、誰にも言うなよ。
kono koto, dare ni mo iu na yo
Don't tell anyone about this, okay? (insistent, but between friends)
明日の集合時間、忘れるなよ。
ashita no shūgō jikan, wasureru na yo
Don't forget tomorrow's meeting time, alright?
Common mistakes
❌ 食べな。
tabe na
Wrong if you mean 'don't eat' — masu-stem + な is the ENCOURAGING command 'go on, eat.'
✅ 食べるな。
taberu na
Don't eat (it). (prohibitive = dictionary form + な)
The single most common slip: attaching な to the masu-stem while intending a prohibition. It flips the meaning to its opposite.
❌ 行きな。
iki na
Wrong for 'don't go' — this means 'go on, go.' The prohibitive is dictionary form + な.
✅ 行くな。
iku na
Don't go.
❌ ここに入りますな。
koko ni hairimasu na
Incorrect — the prohibitive never attaches to the polite ます form. Use the plain dictionary form.
✅ ここに入るな。
koko ni hairu na
Don't come in here.
❌ 先生、心配するな。
sensei, shinpai suru na
Rude — bare 〜な barked at a teacher. Use the polite negative request instead.
✅ 先生、心配しないでください。
sensei, shinpai shinai de kudasai
Please don't worry, sensei.
❌ 走るな！
hashiru na
If you meant to cheer a runner on, this is the opposite — it means 'Don't run!' To urge someone on, use the imperative 走れ or the coaching 諦めるな.
✅ 諦めるな、走れ！
akirameru na, hashire
Don't give up — run!
Key takeaways
- Prohibitive = dictionary form + な: 行くな, 見るな, するな, 来るな. No sound changes, no exceptions.
- It is blunt and forceful — warnings, emergencies, signs, coaching, rough male speech. Not for anyone you respect.
- The polite negative command is 〜ないで（ください）, not 〜な.
- Do not confuse it with the encouraging な (masu-stem + な = "go on, do it"): 食べるな ("don't eat") vs 食べな ("eat up") differ only by る.
- A third な — emotive, on adjectives and だ (いいな, 安いな) — means "…, huh," not a command.
Now practice Japanese
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Start learning Japanese→Related Topics
- The Plain Imperative 〜ろ / 〜えN4 — How to form the blunt plain-imperative 命令形 and — more importantly — where it actually lives: signs, sports, orders, and anger.
- 〜なさい: The Softened CommandN4 — How the masu-stem plus なさい gives a firm but caring downward command — the parent-to-child, teacher-to-pupil imperative.
- 〜ないでください: Negative RequestsN4 — The negative counterpart of てください — built on the ないで negative te-form — for asking someone please not to do something, plus its casual drop 〜ないで and the firmer 〜てはいけない.
- Imperative 命令形 & Prohibitive な: TableN3 — The blunt-command forms in one table — 五段 shift to the え-row (書け), 一段 add ろ/よ (食べろ/食べよ), する→しろ/せよ, 来る→来い, plus the prohibitive dictionary＋な (行くな) and how it differs from the softening ます-stem＋な (食べな).