while doing (two actions at once, same subject)
Form: verb ます-stem + ながら. 食べます → 食べながら, 聞きます → 聞きながら, する → しながら, 来る → 来ながら.
Meaning: two actions happen simultaneously and are performed by the same person. The action in the main (second) clause is the primary one — the ながら-clause is the backdrop. 音楽を聞きながら勉強する = I study (main) while music-listening (backdrop). Reversing it changes emphasis.
Key constraint: same subject only. To express X does A while Y does B, use 間に or うちに instead — 父が寝ている間に、私は掃除した while dad was sleeping, I cleaned.
vs. 〜つつ: same meaning, literary/formal register — appears in essays, novels, news. Also carries a while also… concessive nuance (知りつつ黙っていた stayed silent even while knowing). vs. 〜間 / 〜間に: describes a time span (during), not a simultaneous action by one person.
Furigana is above every kanji; the pattern is already filled in.
音楽を聞きながら勉強する。
I study while listening to music.
歩きスマホを見ないで。
Don't look at your phone while walking.
コーヒーを飲みながら本を読むのが好きだ。
I like reading a book while drinking coffee.