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N5Grammar, one piece at a time · Sep 13, 2026

は vs が: the rule that is never broken, and four that usually hold

は says "here is what we're talking about." が says "this is the one." The fastest way in is not a definition but a rule with no exceptions: a question word never takes は, and the answer to a が-question takes が.

This is the question learners ask more than any other, and most explanations fail the same way — they give a definition ("topic" vs "subject") that is accurate and does not help you choose in the moment. So start with the one rule you can apply without thinking, then add the tendencies.

The basics

The rule with no exceptions: question words take が

だれ, なに, どれ, いつ, どこ — when a question word is the subject, it takes が. Never は.

だれましたか。 。○ だれましたか。 — Who came?

And the answer takes が too, because the answer occupies the same slot:

田中たなかさんがました。 — Tanaka came. (answering "who?")

Now compare the same sentence with は:

田中たなかさんはました。 — As for Tanaka, he came. (answering "did Tanaka come?" — Tanaka was already the subject of conversation)

Both are correct Japanese. They answer different questions. This is the whole distinction in miniature: が supplies the missing piece, は comments on a piece that is already on the table.

The same applies to every question word: なにがありますか, どれがいいですか, いつがいいですか.

New information takes が; known information takes は

This is the tendency that the question-word rule is a special case of.

昔々むかしむかし、おじいさんとおばあさんいました。おじいさんやまきました。 — Once upon a time there were an old man and an old woman. The old man went to the mountain.

Every Japanese folk tale opens exactly like this, and it is the clearest demonstration in the language. The first mention takes が — the characters are new, they are the information. The second mention takes は — now we know who they are, and the sentence is about what they did.

あ、ねこがいる。 — Oh, there's a cat. (new — you just noticed it) そのねこしろいです。 — That cat is white. (known — we have established the cat)

If you are introducing something, reach for が. If you are saying something about something already established, reach for は.

は is not a subject marker at all

This trips up learners who were taught "は marks the subject." It does not. It marks the topic, and a topic can be anything.

わたし寿司すしきです。 — I like sushi. (わたし is the topic; 寿司すし is grammatically the subject of き) そのほんみました。 — That book, I read. (the book is the object, promoted to topic) 明日あしたいそがしいです。 — Tomorrow I'm busy. (the topic is a time)

は replaces が or を when that word becomes the topic — which is why you rarely see わたしはが or ほんはを. The same swallowing behaviour shows up with さえ and with も: they all sit in the same slot and push が and を out.

Beyond the basics

は does contrast; が does "it's this one"

Both particles carry an extra flavour, and the flavours are opposites.

は implies contrast — it quietly suggests other cases might differ:

コーヒーはみません。 — I don't drink coffee. (…but I might drink tea) 今日きょうきません。 — I'm not going today. (…other days, maybe)

が is exhaustive — it says "this one, and not the others":

わたしがやります。I'll do it. (nobody else — I'm volunteering, or claiming it) これがいいです。This is the one I want. (chosen from among options)

This is why わたしがやります can sound assertive while わたしはやります sounds like a plain statement of your own plan. Learners who default to が for "I" end up sounding like they are constantly volunteering for things.

が inside a clause, は outside it

Inside a clause that modifies a noun, the subject takes が, never は.

わたしつくったケーキ — the cake I made the cake I made✗ わたしつくったケーキ

The reason is that は belongs to the whole sentence, not to a piece of it — it announces the topic of everything that follows. A relative clause is a piece, so it cannot host a topic.

田中たなかさんがいたほん面白おもしろいです。 — The book Tanaka wrote is interesting. (が inside, は outside)

This is one of the few は/が questions with a mechanical answer, and it is worth over-learning: if the subject sits inside a modifying clause, it is が.

ぞうはなながい — two markers, one sentence

The famous example, and it stops being strange once you see the two jobs separately.

ぞうはなながい。 — Elephants: the nose is long.

は sets the frame (we are talking about elephants). が points inside the frame at what is actually long. Nothing is competing — they are doing different jobs at different levels.

日本にほん電車でんしゃ便利べんりです。 — In Japan, the trains are convenient. わたしあたまいたい。 — I have a headache. (literally: as for me, the head hurts)

That last pattern is how Japanese handles most body-and-feeling sentences, and once you have it, a whole class of sentences opens up.

The words that demand が

A specific group of adjectives and verbs takes が where English uses a direct object. This catches everyone.

Word Meaning Example
き / きら like / dislike 寿司すしきです
上手じょうず / 下手へた good at / bad at 日本語にほんご上手じょうずですね
ほしい want (a thing) みずほしい
〜たい want to (do) みずみたい
わかる understand 意味いみわかりません
できる can do 日本語にほんごできます
ある / いる exist 時間じかんありません

寿司すしきです is wrong. So is 日本語にほんご上手じょうずです. These are not verbs taking objects in Japanese — they are adjectives describing a state, and the thing being liked or understood is grammatically the subject.

〜たい is the interesting one: both みずみたい and みずみたい are heard, and が is the traditionally correct form. Use が and you will never be wrong.

Why negatives attract は

Negative sentences pull は toward them, because a negative almost always implies a contrast.

さけみません。 — I don't drink alcohol. 時間じかんがありません。 — There's no time. 時間じかんはありません。 — There's no time for that. (contrastive — implies time exists for other things)

The middle sentence is a flat statement of fact. The third is a polite refusal. Same words, and the particle is doing all the work — which is a good example of why this pair rewards attention long after you can pass a test on it.

How does it sound in anime?

が in its exhaustive sense carries a lot of dramatic dialogue, because "it is this one" is inherently a declaration:

おれがやる。I'll do it. (claiming it — nobody else) まえ犯人はんにんだ。You're the culprit. これが最後さいごだ。This is the last one.

Swap those to は and the drama evaporates: おれはやる is just "I'm going to do it," a statement about your plans. The が is what makes it a claim against everyone else in the room.

Common mistakes

  • だれは / なには. A question word as subject always takes が. This one has no exceptions, so learn it first.
  • は inside a relative clause. わたしつくったケーキ is wrong; it must be わたしつくったケーキ. は belongs to the whole sentence.
  • 寿司すしきです. き, きらい, 上手じょうず, 下手へた, ほしい, わかる, できる and ある/いる all take が.
  • Overusing が for "I." わたしがやります claims the job exclusively. For an ordinary statement about yourself, わたしは.
  • Thinking は marks the subject. It marks the topic, which can be an object (そのほんみました) or a time (明日あしたいそがしい).
  • Treating the choice as random. It never is. If a native speaker changes your は to が, there is a reason, and asking what changed in the meaning is the single fastest way to learn this pair.

The four tendencies, plus the rule

Situation Particle Why
Question word as subject The rule — no exceptions
First mention, new information It is the information
Later mention, known thing Now it's the topic
Subject inside a modifying clause は can't live inside a clause
Contrast ("as for X, at least") は implies others differ
"This one and not the others" が is exhaustive
き / 上手じょうず / ほしい / わかる / ある These take が, not を

Practice

Answers are hidden — build yours first, then open. Questions 2 and 3 are a pair: the same sentence, two particles, two different questions being answered.

1. Fill in: だれ( )ましたか。

Show answer

だれましたか。A question word as subject always takes が. This is the one rule in は/が with no exceptions.

2. What question does 田中たなかさんがました answer?

Show answer

"Who came?" — が supplies the missing piece. The answer to a が-question takes が.

3. What question does 田中たなかさんはました answer?

Show answer

"Did Tanaka come?" — は comments on something already on the table. This is the pair to question 2: same words, and the particle tells you what was being asked.

4. Fill in the folk-tale opening: 昔々むかしむかし、おじいさん( )いました。おじいさん( )やまきました。

Show answer

が, then は — first mention is new information, so が. Second mention is now known, so は. Every Japanese folk tale opens exactly this way.

5. Something is wrong here: わたしつくったケーキ。

Show answer

わたしつくったケーキ — the subject of a clause that modifies a noun always takes が. は announces the topic of a whole sentence and cannot sit inside a piece of one.

6. Something is wrong here: 寿司すしきです。

Show answer

寿司すしきですき is an adjective, not a verb taking an object. きらい, 上手じょうず, 下手へた, ほしい, わかる, できる and ある/いる behave the same way.

7. What is the difference between わたしはやります and わたしがやります?

Show answer

Statement vs claimわたしはやります says what you plan to do. わたしがやります says you and nobody else will do it. Defaulting to が makes you sound like you are volunteering constantly.

8. Explain ぞうはなながい.

Show answer

は sets the frame, が points inside it — "as for elephants, the nose is long." The two particles work at different levels, so they are not competing.

9. What is the difference between 時間じかんがありません and 時間じかんはありません?

Show answer

Fact vs polite refusal — が states plainly that there is no time. は adds contrast: no time for that, implying there is time for other things.

10. Say "I have a headache" using the 〜は〜が pattern.

Show answer

わたしあたまいた — literally "as for me, the head hurts." This frame handles most sentences about bodies and feelings in Japanese.

FAQ

Is there a single rule I can always trust? Yes, one: a question word as subject takes が, and so does its answer. Everything else in は/が is a strong tendency rather than a law, which is why starting with the exceptionless rule is worth more than starting with definitions.

Can a sentence have both は and が? Constantly, and it is not a mistake: ぞうはなながい, わたし日本語にほんごがわかります, 日本にほん電車でんしゃ便利べんりです. は frames, が points inside the frame.

Can a sentence have neither? Yes — Japanese drops whatever is obvious. きます, さむいね and かりました are complete sentences. Leaving out a subject you have already established is normal and sounds natural, where repeating わたしは every sentence sounds like a textbook.

Is が ever used for objects? In the specific group above, yes — みずがほしい, 日本語にほんごがわかります. Grammatically those nouns are subjects, even though English translates them as objects. It is easier to memorise the list than to reason about it.

Does は always come first in a sentence? Usually, because the topic frames everything after it. But a contrastive は can sit further in: 今日きょうはコーヒーはみません ("today, coffee at least, I'm not drinking"). Two は in one sentence almost always means the second is contrastive.

Why do textbooks say は marks the subject? Because in the simplest sentences — わたし学生がくせいです — the topic and the subject happen to be the same word, so the shortcut works for a few chapters. It breaks the moment you meet そのほんみました, where the topic is the object.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab — the first column becomes the front, the second the back.

誰	だれ — who
来る	くる — to come
昔々	むかしむかし — once upon a time
山	やま — mountain
猫	ねこ — cat
白い	しろい — white
寿司	すし — sushi
好き	すき — liked, likeable
嫌い	きらい — disliked
上手	じょうず — good at
下手	へた — bad at
分かる	わかる — to understand
意味	いみ — meaning
時間	じかん — time
本	ほん — book
作る	つくる — to make
面白い	おもしろい — interesting
象	ぞう — elephant
鼻	はな — nose
長い	ながい — long
電車	でんしゃ — train
便利	べんり — convenient
頭	あたま — head
痛い	いたい — painful
お酒	おさけ — alcohol
犯人	はんにん — culprit
最後	さいご — the last one

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime. This is the question I get asked most, and the honest answer is that nobody learns it from a definition — what works is collecting sentence pairs where only the particle changes, and asking each time what moved.

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Sources: the author's own lessons and standard reference grammars.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N5

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