Japanese ない-Form (Plain Negative)

In Brief

The ない-form is the plain negative form of a Japanese verb: 書く becomes 書かない (“do not write”), and 食べる becomes 食べない (“do not eat”). Godan verbs change their final kana to the corresponding a-row kana before ない; ichidan verbs drop る and add ない. The main irregular forms are する → しない and 来る → 来ない（こない）.

Overview

The ない-form says that an action does not happen, will not happen, or is not generally true. It belongs to the plain style—the set of forms used in casual conversation and inside many larger sentence patterns. For example, 今日は行かない can mean “I’m not going today,” while 肉を食べない人 means “a person who does not eat meat.” Japanese normally leaves the subject unstated when the context makes it clear.

This is a core A2 pattern because it is both a complete sentence ending and a building block. You will meet it before expressions such as ないでください (“please don’t”), なければならない (“must”), and ないように (“so that … not”). Unlike English, Japanese does not add a separate word like “do not.” The negative meaning is built into the verb ending itself.

The beginner rule is straightforward once you know whether a verb is godan or ichidan. These are conjugation classes—groups of verbs that change endings in different ways. First learn the regular patterns and four high-frequency special forms. Later sections explain how ない changes in longer constructions and why a form such as 食べていない is not simply the same as 食べない.

How It Works

First identify the verb group

Japanese dictionaries list verbs in the dictionary form, such as 書く, 読む, or 食べる.

• Godan verbs change their final kana to another kana in the same consonant column.
• Ichidan verbs usually end in いる or える. Their final る is removed before an ending is attached.
• Irregular verbs must be memorized individually.

The いる/える spelling is a useful clue, not a perfect test. Common godan exceptions include 入る（はいる, “enter”), 走る（はしる, “run”), 帰る（かえる, “return”), 切る（きる, “cut”), 知る（しる, “know”), and 要る（いる, “need”). Learn an unfamiliar verb together with one conjugated form, not from its final る alone.

Godan verbs: move to the a-row and add ない

For a godan verb, replace the final u-row kana with the corresponding a-row kana, then add ない. The one visually unusual case is う: it changes to わ, not あ.

Dictionary ending	ない-form ending	Example	Meaning
う	わない	買う → 買わない	do not buy
く	かない	書く → 書かない	do not write
ぐ	がない	泳ぐ → 泳がない	do not swim
す	さない	話す → 話さない	do not speak
つ	たない	待つ → 待たない	do not wait
ぬ	なない	死ぬ → 死なない	do not die
ぶ	ばない	遊ぶ → 遊ばない	do not play / hang out
む	まない	読む → 読まない	do not read
る	らない	帰る → 帰らない	do not return

Thus 行く becomes 行かない, 分かる becomes 分からない, and 言う becomes 言わない. The change depends on the final kana, not on how the verb happens to be translated into English.

Ichidan verbs: drop る and add ない

Remove the final る and attach ない.

Dictionary form	Stem	ない-form	Meaning
食べる	食べ	食べない	do not eat
見る	見	見ない	do not see / watch
起きる	起き	起きない	do not get up
教える	教え	教えない	do not teach / tell

Do not change the kana before る to the a-row. 食べる is 食べない, not 食ばない.

Irregular and special verbs

Dictionary form	ない-form	Meaning	Note
する	しない	do not do	Irregular
来る（くる）	来ない（こない）	do not come	Irregular; the reading changes
ある	ない	there is not / do not have	Special negative, not あらない

Compounds ending in する follow する: 勉強する → 勉強しない, 予約する → 予約しない.

Plain negative and polite negative

ない is plain. In a polite conversation, the usual sentence ending is ません.

Japanese	English	Note
コーヒーを飲まない。	I don’t drink coffee.	Plain; natural with friends or as an inner statement
コーヒーを飲みません。	I don’t drink coffee.	Polite

Plain does not necessarily mean rude. Plain forms are also required inside clauses, even when the sentence as a whole is polite: 肉を食べない人です means “They are a person who does not eat meat.” The final です makes the overall statement polite.

Examples in Context

Japanese	English	Note
今日は行かない。	I’m not going today.	Casual sentence ending; the context supplies “I”
朝はコーヒーを飲まない。	I don’t drink coffee in the morning.	Habit or general choice
弟は魚を食べない。	My younger brother doesn’t eat fish.	Godan 食べる? No: 食べる is ichidan, so る is dropped
週末は仕事をしない。	I don’t work on weekends.	Irregular する → しない
明日は家に来ない？	Aren’t you coming to my place tomorrow?	Rising intonation makes a casual negative question
この店にはもう来ない。	I won’t come to this shop again.	Present plain negative can refer to a future decision
分からないことがあります。	There are things I don’t understand.	The plain negative clause modifies こと
肉を食べない人もいます。	Some people do not eat meat.	食べない modifies 人
まだ食べていない。	I haven’t eaten yet.	Negative ている; often describes an action not completed yet
その映画は見なかった。	I didn’t see that movie.	Past plain negative: ない → なかった
名前を書かないでください。	Please don’t write your name.	ないでください asks someone not to act
パスポートを忘れないようにしてください。	Please make sure you don’t forget your passport.	ないように expresses prevention or a goal
明日は早く起きなければならない。	I must get up early tomorrow.	Literally, “if I do not get up, it will not do”

In the third row, note that 食べる is an ichidan verb despite ending in る: 食べない is formed by dropping る. This is exactly why learning verb groups matters more than applying one spelling rule to every verb.

Common Mistakes

Adding ない directly to a godan dictionary form

• Wrong: 書くない
• Right: 書かない
• Why: A godan verb must move from its final u-row kana to the matching a-row kana before ない: く → か.

Changing う to あ instead of わ

• Wrong: 買あない
• Right: 買わない
• Why: Godan verbs ending in う use わない. Remember the pattern 買う → 買わない and 言う → 言わない.

Treating every る-verb as ichidan

• Wrong: 帰ない
• Right: 帰らない
• Why: 帰る is godan, so る changes to ら. Many いる/える verbs are ichidan, but common exceptions must be learned individually.

Using あらない as the ordinary negative of ある

• Wrong: 時間があらない。
• Right: 時間がない。
• Why: The ordinary negative of ある is simply ない: “There is no time” or “I have no time.”

Using plain ない as the final form in a formal exchange

• Less appropriate to a customer: 今日は営業しない。
• Better: 今日は営業しません。
• Why: ない is grammatically correct but plain. Use ません as the sentence ending when the situation calls for polite speech. A plain form can still appear inside a polite sentence.

Confusing 食べない with 食べていない

• Different meanings: 朝ご飯を食べない。 / まだ朝ご飯を食べていない。
• Translations: “I don’t eat breakfast.” / “I haven’t eaten breakfast yet.”
• Why: 食べない commonly states a habit, choice, or future non-action. 食べていない negates the ている construction and, with まだ, often says an expected action has not been completed.

Usage Notes

Time comes from context

Japanese non-past forms cover both present and future. 行かない can mean “I don’t go,” “I’m not going,” or “I won’t go.” Time words and the situation decide the best English translation:

• 毎週は行かない。 — “I don’t go every week.”
• 今日は行かない。 — “I’m not going today.”
• 来年は行かない。 — “I won’t go next year.”

English learners often look for separate equivalents of “don’t,” “isn’t going,” and “won’t.” Japanese frequently uses the same ない-form for all three.

Casual negative questions depend on tone and context

行かない？ can ask “Aren’t you going?” or work as an invitation like “Want to go?” In speech, intonation and context make the intention clear. The expanded 行きませんか is a polite invitation. Avoid assuming that every negative question expresses surprise or disagreement in the English way.

ない can connect to nouns and other grammar

A plain verb can directly modify a noun: 読まない本 is “a book that [someone] does not read,” and 来ない人 is “a person who is not coming.” There is no relative pronoun equivalent to English “who” or “that.” The negative clause simply comes before the noun.

The ない-form is also selected by many fixed patterns. In such cases, do not replace it with ません merely because the complete sentence is polite: 忘れないようにしてください is correct, not 忘れませんようにしてください for the ordinary instruction “Please make sure not to forget.”

Beyond the Basics / Advanced Use

You do not need to master every form in this section at A2, but recognizing them will make later grammar much easier.

ない behaves much like an い-adjective

The negative ending changes in predictable ways:

Function	Form from 食べない	Typical meaning
Non-past negative	食べない	do not / will not eat
Past negative	食べなかった	did not eat
Connecting form	食べなくて	not eating; because [someone] did not eat
Conditional	食べなければ	if [someone] does not eat

This explains forms that may initially look unrelated. 行かなかった is the past negative of 行く. 行かなければならない means “must go,” built from “if [one] does not go, it will not do.” In casual speech, なければ may contract in patterns such as 行かなきゃ, but learn the full form first.

ないで and なくて are not interchangeable

Both can connect negative ideas, but they often do different jobs.

• 朝ご飯を食べないで出かけた。 — “I went out without eating breakfast.”
• 朝ご飯を食べなくて、おなかがすいた。 — “Because I didn’t eat breakfast, I got hungry.”

ないで often means “without doing” or appears in requests such as 心配しないで (“don’t worry”). なくて often links a reason, state, or description. The distinction has subtleties, but this basic contrast is a reliable starting point.

Written ぬ and ず

Formal writing, set phrases, and literary language may use older negative forms based on ぬ or ず: 知らぬ (“not knowing / unknown”) and 食べずに (“without eating”). They are not the default neutral conversational negatives. Recognize them as later stylistic alternatives rather than substitutes you need for ordinary A2 speech.

The scope of negation can be ambiguous

Japanese often omits subjects and other information, so a short sentence such as 全部食べない can be interpreted from context. It may mean “I won’t eat all of it” or, in some contexts, “I won’t eat any of it.” Speakers can clarify with forms such as 全部は食べない (“I won’t eat all of it”) or 何も食べない (“I won’t eat anything”). Particles and context show what exactly is being denied.

Practice Tips

1. Make a three-column verb list. Write the dictionary form, verb group, and ない-form for ten frequent verbs: 行く → godan → 行かない; 食べる → ichidan → 食べない. Include at least one verb for every godan ending and several る-verb exceptions.
2. Transform complete sentences. Change 毎日新聞を読む into 毎日新聞を読まない, then into the polite 毎日新聞を読みません. This trains both conjugation and register instead of isolated endings.
3. Listen for what follows ない. In conversations or subtitles, collect examples of ない, ないで, なかった, and なければ. Mark whether each one is a sentence ending, modifies a noun, or begins a larger pattern.

Related Concepts

• Prerequisite: Plain/Dictionary Form — introduces the plain style and the dictionary forms from which the ない-form is built.
• Next step: ように (Purpose/Manner) — uses forms such as 忘れないように to express a goal or prevention: “so that … not.”