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lukewarm; tepid
half-hearted; vague; weak
lenient; mild; soft
生温いビールは飲む気がしないものだ。
Lukewarm beer is something I don't feel like drinking.
長時間放置していたスープが生温かった。
The soup that had been left out for a long time was lukewarm.
淹れたばかりなので、コーヒーは生温くない。
The coffee isn't lukewarm since it was just brewed.