Phonosemantic compound. 彗 represents the sound and 日 represents the meaning. Based on the original meaning "to scorch". The current meaning is a phonetic loan.
う
Example sentences
書道を習うのは楽しい。 — Learning calligraphy is fun.
どうしてフランス語を習うの？ — Why learn French?
エスペラント語を習うのは楽しい。 — Esperanto is a fun language to learn.
どうやってエスペラント語を習うの？ — How are you learning Esperanto?
なんでフランス語を習うのやめたの？ — Why did you stop learning French?