～な（禁止）

How it works

Put な directly after the dictionary form of a verb and you have the bluntest prohibition in Japanese: 行くな (don't go), 食べるな (don't eat), するな (don't do it), 来るな (don't come). Nothing conjugates; the verb stays in plain form for every group, including する and 来る.

Because it is so direct, ～な lives in three places: warning signs (入るな, 触るな, 押すな), rough casual talk (a coach to players, a parent to a child, close male friends, an angry boss) and quoted speech (「泣くな」と言われた). Used on a colleague, a shopkeeper or a teacher it would sound like shouting, so the everyday way to tell someone not to do something is ～ないで or ～ないでください.

Adding よ softens it into friendly reassurance rather than an order, especially with verbs of worrying, laughing or crying: 心配するなよ (hey, don't worry), 笑うなよ (don't laugh, okay?).

Watch the two な's

Japanese has another verb + な: verb stem + な (食べな, 早く行きな) is a clipped ～なさい and means do it. The prohibition is always dictionary form + な: 食べるな. The only visible difference is the る (or う, く, す…) before な.

Examples

• ここで泳ぐな。危ないよ。（ここ で およぐ な。 あぶない よ。） — Don't swim here. It's dangerous.
• 心配するなよ、きっとうまくいくよ。（しんぱい する な よ、 きっと うまく いく よ。） — Don't worry, it'll work out.
• 「押すな」と書いてありますよ。（「おす な」 と かいて あります よ。） — It says 'Do not push'.
• 二度と遅れるな。（にど と おくれる な。） — Don't ever be late again.
• 芝生に入るな。（しばふ に はいる な。） — Keep off the grass.
• 嘘をつくな。（うそ を つく な。） — Don't lie.

Compare with

～ないでください

The neutral, polite way to forbid or to ask someone not to do something. ここに車を止めないでください is what the shop owner says; 止めるな is what the sign says.

～てはいけない

States a rule or an impersonal ban rather than barking at a person: ここで写真を撮ってはいけません (photography is not allowed here). It has a polite form (いけません) and a plain one (いけない／だめ), while ～な has no polite version at all.

Verb stem + な (～なさい)

食べな = eat, a clipped 食べなさい. Same particle shape, opposite meaning; see the traps below.

Traps for Spanish, English and French speakers

• Spanish «no corras» and French «ne cours pas» are ordinary commands you can say to a friend, so learners drop 走るな on a coworker; in Japanese that is a bark or a sign. Say 走らないで, or 走らないでください to anyone you use です／ます with.
• 食べな (verb stem + な) is a clipped 食べなさい and means 'eat!', while 食べるな (dictionary form + な) means 'don't eat!'. One る flips the meaning, so listen for it.
• Sentence-final な is not always a prohibition. After an adjective, noun or だ it is an exclamation (暑いな 'it's hot, huh', 便利だな 'how handy'), and even after a dictionary-form verb it can be one: よく食べるな is 'wow, you eat a lot', not 'don't eat much'. The exclamation is usually drawn out (なあ) and comments on something; the prohibition is short, sharp and aimed at the listener.
• な has no polite version and cannot be softened with ください: 触るなください ✗. Learners who want 'please don't' must switch to the ない-form, and even then very often drop the で: 触らないください ✗. The polite prohibition is 触らないでください.