yoru wa furo ni hairu kedo, asa wa shawaa dake ni suru.

At night I take a bath, but in the morning I only take a shower.

Breakdown of yoru wa furo ni hairu kedo, asa wa shawaa dake ni suru.

• は: topic particle
• 朝あさ: morning
• 夜よる: night
• 入はいる: to enter

Questions & Answers about yoru wa furo ni hairu kedo, asa wa shawaa dake ni suru.

Who is the subject here? There’s no “I.”

Japanese often drops the subject when it’s clear from context. In this sentence it most naturally means “I,” but depending on context it could also mean “you,” “we,” or people in general.

What does the particle は do after 夜 and 朝?

は marks the topic and is contrastive here: “As for nights … but as for mornings …” Putting は after time words like 夜 and 朝 is a common way to set up a contrast in habits.

Can I use 朝に or 夜に instead of 朝は and 夜は?

Use に for specific, scheduled times (e.g., 明日の朝に). For general habits, 朝/夜 usually appear without に, and は is perfect for contrast: 夜は… 朝は…. You could say 夜に in a specific one-time context, but for a habitual contrast, は is more natural.

Why does 風呂に入る mean “take a bath”? It literally looks like “enter the bath.”

That’s exactly the Japanese idiom: “to enter the bath” = “to take a bath.” Note the related but different verb お風呂を入れる, which means “to run/fill the bath.”

Why is the particle に used with 入る, not を or で?