Negatives ない・いない

Once you can say something exists with ある and いる, the very next thing you need is how to say it doesn't. The negatives are ない ("there isn't / I don't have") for things and いない ("there's no one / nothing alive") for living beings. They negate an existence claim — whether something is there at all — which is a different job from negating the copula です (whether something is such-and-such). Keep those two apart and the negatives are simple.

The four forms

Both verbs have a plain and a polite negative. The plain forms are the ones you'll hear most in conversation; the polite forms belong to careful or formal speech.

That last one shows the pattern in both polarities at once: いません for the sister who isn't there, います for the brother who is. And note the animacy rule carries straight through the negative — people and animals take いない/いません, never ない/ありません.

ない does double duty — and that's the key insight

Here is the fact that makes the whole system click. The ない that means "there isn't" is the very same ない that turns any other verb negative — 食べない ("doesn't eat"), 行かない ("doesn't go"), 分からない ("doesn't understand"). They are not two look-alikes; they are historically one word: an い-adjective meaning "non-existent."

Because they share one origin, they inflect identically. The standalone ない and the suffix ない both behave like い-adjectives: past なかった, te-form なくて.

So if you already know how to negate verbs, you already know how ない conjugates for existence — it's the same machine. The deeper irregularity behind this (why ある's negative is ない rather than the "regular" ×あらない) has its own page: ある's Irregular Negative ない.

〜はない: negating for contrast and emphasis

Swap が for は in a negative and you add a note of contrast or emphasis — "that particular thing isn't there (whatever else might be)." This is extremely common, because denials so often single one thing out.

In 犬はいるが猫はいない the two はs set the animals against each other; in 質問はありませんか (a phrase every teacher says at the end of a lesson) は gently spotlights questions as the thing being asked about. The bare が-version 質問がありませんか is fine too, but the は-version is the idiomatic classroom default.

誰も / 何も: "no one" and "nothing"

To say no one or nothing exists, pair the question word with も and keep the verb negative: 誰も + いない, 何も + ない. The も is what turns "someone/something" into a sweeping "not a soul / not a thing."

The verb must stay negative here — 誰も and 何も cannot appear with a positive existence verb. (誰か "someone" and 何か "something," by contrast, go with positive verbs: 誰かいる "there's someone there.")

The trap: existence negative vs copula negative

This is the error worth burning in. "The cat isn't in the room" is an existence statement — negate it with いない. But English's flat "isn't" tempts learners into the copula negative じゃない / ではない, which means "isn't (equal to / such-and-such)." Those are not interchangeable.

The first denies that the cat is present; the second denies that something is a cat. Reach for じゃない to locate the cat (×猫は部屋じゃない) and you accidentally say "the cat isn't a room."

Common mistakes

The first four are the recurring slips: over-regularizing ある to ×あらない, mixing up the animacy of the verb, and confusing absence (いない) with identity-negation (じゃない). The fifth is a direct consequence of the double-duty insight — because ない is an い-adjective, you must past-tense it like one (なかった), not with the copula でした.

Key takeaways

• ある → ない / ありません; いる → いない / いません. Animacy still decides which pair.
• The existence ない and the verb-negating suffix ない are the same い-adjective — so both inflect as なかった / なくて.
• 〜はない adds contrast or emphasis; 誰も…いない / 何も…ない mean "no one / nothing" and force a negative verb.
• Don't confuse the existence negative (ない/いない, "isn't there") with the copula negative (じゃない, "isn't such-and-such").