【Topic maker】The Difference Between "が(ga)" and "は(wa)"

 

1. Basic Functions

が (ga)

• Marks the subject of the sentence (who/what is doing the action or in focus).

• Used when introducing new information or when the subject itself is the focus.

• Often answers the question “Who/What … ?”

Example 1:

X: だれが　来ましたか。(Dare ga kimashita ka?) (Who came?)

Y: 田中さんが　来ました。(Tanaka-san ga kimashita.) (Tanaka came.) 

Example 2 :

・テーブルの上に　猫がいます。(Tēburu no ue ni neko ga imasu.) (There is a cat on the table.)

★★★Subject is focused, new information

---

は (wa)

• Marks the topic of the sentence (what the sentence is “about”).

• Often contrasts, emphasizes, or gives known/background information.

• Often states general facts or habits in a general way.

• Answers the question “As for … ?” / “What about … ?”

 Example1:

• 田中さんは　来ました。(Tanaka-san wa kimashita.) (As for Tanaka, he came.) 
  【Tanaka is the topic, maybe in contrast to others.】

Example 2:

• 猫は　好きです。(Neko wa suki desu.) (As for cats, I like them.)
  【Cats are the topic, maybe in contrast to other animals.】

Example 3:

• 机の上に　犬がいます。その犬は　5歳です。(Tsukue no ue ni inu ga imasu. Sono inu wa gosai desu.) (There is a dog on the desk. The dog is five years old.)
  【The 犬 is already introduced in the first sentence. So in the next sentence, this 犬 is regard as known. 】

Example 4:

• 私は毎日　公園を走ります。(Watashi wa mainichi kouen wo hashirimasu.) (I run in the park everyday.)
  【This sentence is the statement of general fact or topic.】

2. Usage Rules in Context

1. Introducing new subject → use が
   あそこに猫がいます。(Asoko ni nko ga imasu.) (There is a cat over there.)

2. Talking about known subject → use は
   猫はかわいいです。(Neko wa kawaii desu.) (As for cats, they are cute.)

3. Contrast→use は
   日本語は分かりますが、中国語は分かりません。
   (Nihongo wa wakarimasuga, chūgokugo wa wakarimsen.)
   (I understand Japanese, but not Chinese.)

3. Contrast between は and が

Case 1A: Neutral description (new information)

猫が好きです。(Neko ga suki desu.)
(I like cats./It is cats that I like.)

Case 1B: Topic-oriented statement

猫は好きです。(Neko wa suki desu.)
(As for cats, I like them. → maybe in contrast to something else, like “dogs.”)

Case 2A: Neutral description (new information, emphasizing the doer)

村上さんが　車を　運転します。(Murakami-san ga kuruma wo unten shimasu.)
(It’s Mr.Murakami who drives the car. → Emphasis on who is driving. / For example: “Who will drive?” → “Mr. Murkami will.”)

Case 2B: Topic-oriented statement (general or contrastive topic)

村上さんは　車を運転します。(Murakami-san wa kuruma wo unten shimasu.)

(As for Mr.Murakami, he drives a car. → Stating it as a general fact or habit, or in contrast with someone else’s situation. / For example: “What about Mr.Murakami?” → “As for Mr.Murakami, he drives.”)