はContrast marker
Contrastive は presents one person, thing, time, place, or choice in contrast with another stated or contextually clear alternative. It can also limit a claim to one item without saying that the complete opposite is true of everything else.
Making the contrast clear
The clearest pattern places two alternatives in parallel. The comments may be positive and negative, or they may simply describe different facts about the two items.
Keeping another particle
With particles that show such relationships as time or place, keep that particle and add は. This lets you contrast not only people and things, but also settings such as different days or locations.
A limited claim
Sometimes the other alternative is supplied by the conversation rather than repeated in the sentence. In that case, the contrast marker often means roughly “this much is true,” while leaving the other possibility unanswered.
The answer confirms vegetables but does not necessarily say whether the speaker eats meat.
Nearby patterns
Ordinary topic は simply sets up what a sentence is about, while contrastive は points toward an alternative. が normally identifies or marks the subject rather than contrasting it, and も adds an item that shares the same description. The fixed pattern ではなくて explicitly rejects one choice and replaces it with another.
More examples
朝は忙しいですが、夜は暇です。
I am busy in the morning, but free in the evening.
Analyze姉は電車で行きますが、兄は車で行きます。
My older sister goes by train, but my older brother goes by car.
Analyzeパンは買いましたが、牛乳は買いませんでした。
I bought bread, but I did not buy milk.
Analyzeこの部屋では話せますが、隣の部屋では話せません。
We can talk in this room, but not in the next room.
Analyze駅まではバスで行き、駅からは歩きます。
I go as far as the station by bus, and walk from the station.
Analyze田中さんとは話しましたが、山田さんとはまだ話していません。
I spoke with Mr. Tanaka, but I have not spoken with Mr. Yamada yet.
Analyze