Grammar › Particles › を
を — the object marker
One small hook that marks the thing an action happens to — what you drink, watch, read, or buy.
The short version
を attaches to the direct object — the noun on the receiving end of the verb. It marks what gets eaten, drunk, seen or bought, and sits right before the verb. (It's written を but pronounced just like お "o".)
水を飲む — drink water (object = 水)
映画を見る — watch a movie (object = 映画)
Marking what the action hits
Whatever the verb does, を points at the target. Here it marks the movie being watched:
With が-taking verbs too
を marks the object of a normal action verb — but remember a big group of "feeling/ability" words (好き, できる, ある) mark their target with が instead. Here 読む ("read") is a plain action verb, so its object 本 takes を, and the whole act of reading is then liked with が:
私は本を読むのが好きです。
I like reading books. (本を読む = read books)
Watch out
🗣 In casual speech, を is the first thing to go. Between friends it's routinely dropped when the object is obvious — 「ご飯食べた？」 for 「ご飯を食べた？」 ("did you eat?"), 「これ見て」 for 「これを見て」 ("look at this"). The を comes back the moment the sentence turns polite or formal.
を isn't only for objects. With motion verbs it can mark the space passed through or the place left — 道を歩く (walk along the road), 家を出る (leave home). Same hook, "the thing the motion involves".
Next: に — time & destination → · は vs が → · All grammar
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