Japanese Negation: How to Make Negative Sentences

How to Make Negative Sentences in Japanese

So you want to say "no" in Japanese? Well, get ready, because Japanese negation works completely differently from English. The good news is that once you understand the patterns, making negative sentences becomes pretty straightforward. The bad news? You've got multiple verb types to deal with, formal versus informal styles, and a bunch of conjugation rules to memorize.

Here's the thing though: mastering negative forms is absolutely essential for basic conversation. You can't just avoid saying "I don't know" or "I didn't go" forever. Let's break down exactly how Japanese negation works, starting with the basics and working our way up to the trickier stuff.

Understanding Japanese Negation Basics

Japanese uses different negative forms depending on what you're negating. Verbs, adjectives, and nouns all have their own rules. The most common pattern you'll see is adding nai (ない) for informal negation and masen (ません) for formal negation.

Unlike English where you just slap "not" into a sentence, Japanese requires you to conjugate the verb itself into a negative form. Think of it like this: you're transforming the entire word, rather than adding a separate negation word.

The particle wa (は) often appears in negative sentences to mark the topic, just like in regular Japanese sentences. You'll see patterns like "watashi wa tabenai" (私は食べない) meaning "I don't eat" or "I won't eat."

Negative Form for Verbs

Verbs are where most learners spend their time with negation, and for good reason. You'll use negative verb forms constantly in everyday conversation.

Ru-verbs (Group 2 Verbs)

Ru-verbs are the easiest to negate. You literally just drop the ru (る) and add nai (ない) for informal or masen (ません) for formal.

Let's look at taberu (食べる), which means "to eat":

Another example with miru (見る) meaning "to see" or "to watch":

Pretty straightforward, right? The conjugation pattern stays consistent across all ru-verbs.

U-verbs (Group 1 Verbs)

U-verbs require a bit more work. You need to change the final u (う) sound to the corresponding a sound, then add nai (ない) for informal or masen (ません) for formal.

Take kaku (書く) meaning "to write":

Wait, that formal one looks different! For formal negation with u-verbs, you actually use the masu (ます) stem. So kaku becomes kakimasu in formal positive, and kakimasen in formal negative.

Let's try nomu (飲む) meaning "to drink":

The mu (む) changed to ma (ま) for the informal, and we used the masu stem nomi for the formal version.

One more example with hanasu (話す) meaning "to speak":

Here's a quick reference for the sound changes in u-verbs:

That last one trips people up. The verb kau (買う) meaning "to buy" becomes kawanai (買わない), using wa (わ) instead of a (あ).

Irregular Verbs

Japanese has two main irregular verbs that you absolutely need to memorize: suru (する) meaning "to do" and kuru (来る) meaning "to come."

For suru:

For kuru:

These don't follow the normal patterns, so you've just got to drill them until they stick.

Past Tense Negatives

Alright, so you've got present tense negation down. Now let's add past tense into the mix.

For informal past negative, you take the negative form ending in nai (ない) and conjugate nai as if it were an i-adjective. Change the i (い) to katta (かった).

Using taberu (食べる) again:

With kaku (書く):

For formal past negative, you take the masen (ません) form and change it to masen deshita (ませんでした).

Examples:

This pattern holds across all verb types. Once you know the present negative, forming the past negative follows the same rules every time.

Negating Adjectives

Japanese has two types of adjectives, and they negate differently.

I-adjectives

I-adjectives end in i (い) in their dictionary form. To negate them, drop the final i and add kunai (くない) for informal or ku arimasen (くありません) for formal.

Take takai (高い) meaning "expensive" or "tall":

Another example with oishii (美味しい) meaning "delicious":

For past tense, use kunakatta (くなかった) for informal or ku arimasen deshita (くありませんでした) for formal.

Na-adjectives

Na-adjectives work more like nouns. You add ja nai (じゃない) or dewa nai (ではない) for informal negation, and ja arimasen (じゃありません) or dewa arimasen (ではありません) for formal.

Using kirei (きれい) meaning "pretty" or "clean":

The dewa versions sound more formal and are more common in writing, while ja versions are more conversational.

Negating Nouns

To negate a noun, you use ja nai (じゃない) or dewa nai (ではない) for informal, and ja arimasen (じゃありません) or dewa arimasen (ではありません) for formal. This is basically the same as na-adjectives.

You might be wondering: is it dewanai or janai? Both are correct. Dewa nai (ではない) is more formal, while ja nai (じゃない) is conversational. You'll hear ja nai way more often in daily speech.

Examples with gakusei (学生) meaning "student":

The copula desu (です) becomes ja nai desu (じゃないです) in casual polite speech, though technically ja arimasen is more grammatically correct for formal situations.

Answering Questions with Negation

When someone asks you a yes/no question in Japanese, you answer with hai (はい) for yes or iie (いいえ) for no, then typically follow up with the appropriate verb form.

Question: Nihongo wo hanashimasu ka (日本語を話しますか) meaning "Do you speak Japanese?"

Negative answer: Iie, hanashimasen (いいえ、話しません) meaning "No, I don't speak."

You can also just use the negative verb alone without iie in casual conversation. The verb form makes it clear you're saying no.

Here's something that confuses English speakers: if someone asks a negative question like "Don't you like sushi?" and you want to say you DO like it, you still say hai (はい) in Japanese. The logic is different from English. You're confirming or denying the statement itself.

Question: Sushi wa suki ja nai desu ka (寿司は好きじゃないですか) meaning "Don't you like sushi?"

If you like sushi: Iie, suki desu (いいえ、好きです) meaning "No (to your negative assumption), I like it."

If you don't like sushi: Hai, suki ja nai desu (はい、好きじゃないです) meaning "Yes (you're correct), I don't like it."

This trips up a lot of learners, so pay attention to the pattern.

Partial Negation and Double Negatives

Partial negation in Japanese uses words like amari (あまり) meaning "not very" or zenzen (全然) meaning "not at all." These words pair with negative verb forms to express degree.

Amari oishikunai (あまり美味しくない) means "not very delicious." The amari softens the negation.

Zenzen wakaranai (全然分からない) means "don't understand at all." The zenzen emphasizes complete negation.

Double negatives in Japanese work differently than in English. When you use a negative verb with a negative potential form, you're actually creating emphasis rather than canceling out the negation.

For example, ikanai wake ni wa ikanai (行かないわけにはいかない) literally translates to something like "it's not that I can't not go," which means "I have to go" or "I have no choice but to go." These constructions sound formal and are more common in written Japanese or formal speech.

Another pattern uses nai to ikenai (ないといけない) meaning "must do." Literally this is "if you don't do it, it won't work," but it functions as an obligation expression.

Common Mistakes with Japanese Negation

One mistake beginners make is trying to use a separate word for "not" like in English. You can't just stick nai (ない) randomly into a sentence. You need to conjugate the verb properly.

Wrong: Watashi wa taberu nai (私は食べるない) Right: Watashi wa tabenai (私は食べない)

Another common error is mixing up the verb groups. If you treat a u-verb like a ru-verb, you'll create nonsense words. Kaku (書く) doesn't become kakunai. It becomes kakanai (書かない).

Some learners also forget that aru (ある) meaning "to exist" (for inanimate objects) has an irregular negative: nai (ない). Not aranai or arinai, just nai.

Similarly, iru (いる) meaning "to exist" (for animate beings) becomes inai (いない), which follows the ru-verb pattern but looks a bit odd because the stem is so short.

Why Japanese Grammar Uses These Negation Patterns

Japanese grammar builds negation into the verb conjugation system because the language is agglutinative. Meaning, you add suffixes to word stems to change meaning and grammatical function. The negative suffix nai (ない) actually evolved from an adjective, which is why it conjugates like an i-adjective in past tense.

The formal masen (ません) comes from the masu (ます) form, which is itself a verb ending that indicates politeness. Understanding this helps explain why formal negation looks so different from informal negation. They developed from different grammatical sources.

The particle wa (は) often appears in negative sentences because Japanese tends to mark topics more explicitly when making negative statements. You're establishing what you're talking about, then negating the action or state.

Practical Sentence Examples

Let's put this all together with some full sentences you might actually use:

Kyou wa shigoto ni ikimasen (今日は仕事に行きません) meaning "I'm not going to work today." (formal)

Sono eiga wo minakatta (その映画を見なかった) meaning "I didn't watch that movie." (informal)

Kare wa shinsetsu ja nai (彼は親切じゃない) meaning "He isn't kind." (informal)

Nihongo wa muzukashikunai desu (日本語は難しくないです) meaning "Japanese isn't difficult." (casual polite)

Ashita konaide kudasai (明日来ないでください) meaning "Please don't come tomorrow." (polite request)

That last one uses the naide (ないで) form, which is the negative te-form used for requests and commands. Just another conjugation pattern to add to your collection.

Negation in Different Contexts

The level of formality you choose affects which negative form you use. In business settings, you'll stick with masen (ません) forms. With friends, nai (ない) is totally fine. With strangers in service situations, you might use nai desu (ないです) as a middle ground.

Written Japanese, especially in hiragana-heavy texts for learners, will often spell everything out clearly. In real-world Japanese with kanji, you'll see negative verbs like 食べない where the kanji shows the verb root and the hiragana shows the negative ending.

Some dialects have different negation patterns. Kansai dialect, for example, uses hen (へん) for negation instead of nai (ない) in many cases. Tabehenai instead of tabenai. But stick with standard Japanese negation until you're comfortable with the basics.

Moving Forward with Negation

Honestly, the best way to get comfortable with Japanese negation is just to practice. A lot. Make flashcards with verb conjugations. Write out negative sentences. Try to negate everything you see during your study sessions.

Pay attention to negative forms when you're consuming Japanese media. You'll hear nai (ない) and masen (ません) constantly in anime, dramas, and conversations. The more you expose yourself to these patterns, the more natural they'll become.

Don't stress too much about getting every conjugation perfect right away. Even if you mess up and say taberunai instead of tabenai, Japanese speakers will usually understand what you mean. The important thing is to keep practicing and gradually refine your accuracy.

Anyway, if you want to practice spotting these negative forms in real Japanese content, Migaku's browser extension lets you look up words and grammar patterns instantly while watching shows or reading articles. Makes it way easier to learn from actual native content instead of just textbook examples. There's a 10-day free trial if you want to check it out.