は vs が
は marks what you are talking about (the topic); が marks who or what does it (the subject), especially when that is the new or important part.
The difference between は and が, the question every learner asks: topic versus subject, old versus new information, with minimal pairs and a quick check.
Side by side
| は (wa) | が (ga) | |
|---|---|---|
| Job | Topic: "as for X" | Subject: "X is the one that" |
| Information | Already known, background | New, the point of the sentence |
| Question words | Never: not だれは | Always: だれが, 何が |
| Contrast | Yes: 肉は食べない (but fish I do) | No |
| Inside a clause | Rare | Normal: 私が作ったケーキ |
| With 好き, 分かる, ある | Marks the person: 私は | Marks the object: 猫が好き |
Start with the question
The quickest test is to ask what the sentence answers. 「田中さんは来ました」 answers "what about Tanaka?": the news is that he came. 「田中さんが来ました」 answers "who came?": the news is that it was Tanaka.
That is why question words and their answers take が: 「だれが来ましたか。」「田中さんが来ました。」
Both in one sentence
Many sentences have both: は for the topic and が for the subject of the comment. 「象は鼻が長い」: as for elephants, the nose is long. 「私は猫が好きです」: as for me, cats are what I like.
In a clause that describes a noun, the subject takes が, even if the main sentence uses は: 「私が作ったケーキは、おいしい」.
Side-by-side examples
Tap a kanji for its reading.
- 私は田中です。I'm Tanaka.Introducing yourself: you are the topic, your name is the news.
- 私が田中です。I'm the one who's Tanaka.Answering "which of you is Tanaka?": the news is that it is me.
- 雨は降っています。As for rain, it is falling.Odd on its own; it suggests a contrast (snow, however, is not).
- 雨が降っています。It's raining.Reporting what you see: the whole sentence is new.
Quick check
- だれ（ ）窓を開けましたか。
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が · Question words take が. - 私は日本語（ ）分かります。
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が · 分かる takes が for what is understood; は is already on 私. - 肉は食べますが、魚（ ）食べません。
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は · Contrast between two topics takes は.