Normally I can simply say that は (wa) is a topic marker, and が (ga) is a subject marker.
Let’s look at some examples:
1）私は日本人です。
Watashi wa nihonjin desu. → “I am Japanese.”
2）私が日本人です。
Watashi ga nihonjin desu. → “I am Japanese.”
Both can be translated the same way in English. While sentence (1) sounds neutral and natural, sentence (2) emphasizes “watashi” (I).
For example, imagine someone says that your friend is Japanese, but that’s not true — you are the one who is Japanese. In this case, you would use sentence (2) to correct them.
Are you still confused? I always explain to students that what comes after “は” or before “が” is usually something you want to emphasize or highlight. Let’s see another example:
3) 私はりんごが好きです。
Watashi wa ringo ga suki desu. → “I like apples.”
In this sentence, “watashi” (I) is the topic, and “ringo” (apple) is the subject.
What comes after は (wa) is the main information you want to share — in this case, ringo ga suki desu (“I like apples”).
The word before が (ga) — here, ringo — shows what the feeling (liking) is directed toward. In other words, ringo is the focus of the sentence.
💡 Note: In Japanese, the topic can often be omitted.
So you can simply say: りんごが好きです, and it still means “I like apples.”
See? My theory does make sense here.
Comparing “は” (wa)
The particle “は” can also be used to show contrast or comparison — though it depends on the situation.
Let’s say there are two apples on the table:
4) 左のりんごは大きいです。右のりんごは小さいです。
Hidari no ringo wa ookii desu. Migi no ringo wa chiisai desu.
→ The apple on the left is big. The apple on the right is small.
In this situation, you cannot use “が”, because the speaker is comparing two items.
5) 私はりんごは好きですが、オレンジは好きではありません。
Watashi wa ringo wa suki desu ga, orenji wa suki dewa arimasen.
→ I like apples, but I don’t like oranges.
Normally, there is only one topic (“は”) in a sentence, right? But in sentence (5), there are three. The first “は” (after watashi) marks the topic, that means other “は” are used for contrast or comparison.
Neutral statement “が“（ga)
Neutral statements express factual information objectively, without opinions or judgments. In these sentences, は cannot be used:
For example,
6）雨が降っている。
Ame ga futte iru.
→ It is raining.
7）ほら、バスが来ました。
Hora, basu ga kimashita.
→Look, the bus has arrive.
Conclusion
This is a concise overview of the difference between は and が !
I hope you now understand 🙂
Remember:
は topic marker and can indicate contrast
が subject marker and can emphasizes focus or objective facts.