は vs が: Complete Guide to Japanese Subject Particles

Understanding the difference between は (wa) andが (ga) is one of the most important distinctions in Japanese grammar. This comprehensive guide will help you master when and how to use each one correctly.

Grammar Point A

は (wa)

Topic particle

Marks the topic of conversation, shows contrast, used for general statements about known information

Formation: Noun + は / Adjective + は / Adverb + は

Grammar Point B

が (ga)

Subject particle

Marks the grammatical subject, introduces new information, shows emphasis, used in relative clauses

Formation: Noun + が

Quick Comparison Table

Aspect	は	が
Meaning	Topic particle	Subject particle
Usage	Marks the topic of conversation, shows contrast, used for general statements about known information	Marks the grammatical subject, introduces new information, shows emphasis, used in relative clauses
Formation	Noun + は / Adjective + は / Adverb + は	Noun + が
JLPT Level	N5	N5
Function	Topic marker	Subject marker
Information type	Known/established information	New/specific information
Can show contrast	Yes	No
Used in relative clauses	No	Yes
With question words	No	Yes
With adjectives (好き, 欲しい)	No	Yes
Scope	Can cross clause boundaries	Limited to one clause

Key Differences

1

は marks topics, が marks subjects: は shows what you're talking about (the topic), while が shows who or what is doing the action (the grammatical subject). This is the fundamental difference.

2

は for known information, が for new information: Use は when both speaker and listener already know what you're referring to. Use が when introducing new information or answering questions.

3

は can show contrast, が cannot: は has a contrastive function, often translating to 'as for...' or 'but'. が simply marks the subject without any contrastive meaning.

4

が is mandatory in certain constructions: With adjectives like 好き, 欲しい, できる, and in relative clauses, you must use が, not は.

5

Question words always use が: 誰が (who), 何が (what), どれが (which) always use が because they're asking for new, unknown information.

When to Use Which?

Follow this decision guide to choose the right grammar point.

Yes

Use は

No

Use が

No

Yes

Use が

No

Use は

Examples with Explanations

は

私は学生です。

Watashi wa gakusei desu.

が

私が学生です。

Watashi ga gakusei desu.

は

映画は面白かったです。

Eiga wa omoshirokatta desu.

が

映画が面白かったです。

Eiga ga omoshirokatta desu.

が

誰が来ましたか？

Dare ga kimashita ka?

は

田中さんは元気ですか？

Tanaka-san wa genki desu ka?

が

コーヒーが好きです。

Koohii ga suki desu.

は

日本語は分かりますが、中国語は分かりません。

Nihongo wa wakarimasu ga, chuugokugo wa wakarimasen.

Common Mistakes to Avoid

Mistake #1Using は with question words

Correction: Always use が with question words like 誰, 何, どれ

Question words ask for new information, so they need が, not は.

Wrong: 誰は来ましたか？ -- Who came? (incorrect particle)

Correct: 誰が来ましたか？ -- Who came? (correct)

Mistake #2Using が for general statements

Correction: Use は for general, topic-setting statements

When making broad statements about something, は is more natural than が.

Wrong: 今日が暖かいです。 -- Today is warm (unnatural emphasis)

Correct: 今日は暖かいです。 -- Today is warm (natural statement)

Mistake #3Using は with preference adjectives

Correction: Use が with 好き, 欲しい, できる, etc.

These adjectives have a fixed grammar pattern that requires が.

Wrong: この本は欲しいです。 -- I want this book (wrong particle)

Correct: この本が欲しいです。 -- I want this book (correct)

Mistake #4Overusing は when introducing new information

Correction: Use が when answering questions or introducing new facts

When providing new information that the listener doesn't know, が is more appropriate.

Wrong: 新しい先生は田中さんです。 -- The new teacher is Mr. Tanaka (assuming known)

Correct: 新しい先生が田中さんです。 -- The new teacher is Mr. Tanaka (new information)

Memory Tips

Tip 1

Topic vs Subject Visualization

Think of は as setting the stage (topic) and が as the actor (subject). The stage is what we're talking about, the actor is who does the action.

Example: In 'パーティーは田中さんが来ます', the party is the stage (は), Tanaka is the actor who comes (が).

Tip 2

Question Test

If you can ask 'what about X?' then use は. If you're answering 'who/what?', use が.

Example: 田中さんは？(What about Tanaka?) vs 誰が？(Who?)

Tip 3

Contrast Clue

If you can imagine adding 'but' or comparing with something else, use は.

Example: 日本語は分かります(が、中国語は分かりません) - Japanese I understand (but Chinese I don't)

Practice Exercises

Test your understanding with these practice questions. Click on your answer to see if you are correct.

0 / 6 answered

Q1

誰___日本語の先生ですか？

Who is the Japanese teacher?

Q2

私___学生です。

I am a student.

Q3

あの人___田中さんです。

That person is Mr. Tanaka.

Q4

コーヒー___好きです。

I like coffee.

Q5

昨日___雨でした。

Yesterday was rainy.

Q6

日本語___分かりますが、中国語___分かりません。

I understand Japanese, but I don't understand Chinese.

Frequently Asked Questions

What's the basic difference between は and が?

Why is は pronounced 'wa' instead of 'ha'?

When do I use が with adjectives?

Can I use は in relative clauses?

Do native speakers always follow these は/が rules?

Summary

Use は when...

Marks the topic of conversation, shows contrast, used for general statements about known information

Use が when...

Marks the grammatical subject, introduces new information, shows emphasis, used in relative clauses

Pro Tip: The best way to master the difference is through reading and listening practice. Pay attention to how native speakers use these grammar points in context.