もの details
quiet + 'cause
shizuka damono
'cause; but I — a reason pushed back at the hearer, sentence-final
だって、まだ宿題終わってないんだもん。
datte, mada shukudai owattenai n da mon.
But I haven't finished my homework yet! casual
行きたくないなあ。人が多いのは苦手だもの。
ikitakunai naa. hito ga ooi no wa nigate da mono.
I'd rather not go. Crowds just aren't my thing. casual
- na-adjective
- noun
- contraction
- formal
Examples
'cause — the speaker justifies their own position to a hearer who has just questioned it
だって、まだ宿題終わってないんだもん。
datte, mada shukudai owattenai n da mon.
But I haven't finished my homework yet! casual
行きたくないなあ。人が多いのは苦手だもの。
ikitakunai naa. hito ga ooi no wa nigate da mono.
I'd rather not go. Crowds just aren't my thing. casual
仕方がないよ、まだ子供だもん。
shikata ga nai yo, mada kodomo da mon.
You can't blame them — they're still children. casual
私、そういうのは苦手なんですもの。
watashi, sou iu no wa nigate na n desu mono.
I'm simply no good at that sort of thing. neutral
Formation
plain clause + ものattaches to plain clause{NA-stem}だものattaches to na-adjective{N}だものattaches to noun
Variant notes
- もん — the everyday spoken shape, far commoner than もの — だって知らなかったんだもん.
- ですもの — polite-style もの, markedly feminine and old-fashioned — わたくしには分かりませんもの.
Notes
もの／もん reads as childish or intimate; ですもの is not the neutral
escape from that but 女性語, older and markedly feminine. A
written apology reaches for ものだから or ので instead.
Related patterns
Similar
Sentence-final から trails a reason as assurance or warning and is at home in any register (先に帰るね、明日も早いから); もの／もん answers an objection the hearer has just raised and, from an adult, is heard as childish or wheedling — から can close a business message, もん cannot appear in one.
だって opens the turn and もの／もん closes it, which is why they so often bracket the same sentence (だって眠いんだもん) — だって announces that a rebuttal is coming, もの supplies the reason it rests on, and neither does the other's job.
もの／もん pushes back at an objection, actual or anticipated, and orients the whole turn to it (「なんで？」「だって眠いんだもん」); ものだから volunteers the excuse unprompted, next to the apology it props up (遅れてすみません、電車が止まっていたものですから) — both can trail at the end of a turn, only もん requires something to answer.
Lookalikes
Both end a sentence in もの, and the だ is the whole difference — 疲れるものだ states a general truth about how things go, while 疲れるもん gives the speaker's own reason for refusing right now; adding だ to a もん protest turns it into a truism.
Bare もの／もん answers an objection sentence-finally, spoken only outside the formal ですもの variant, with no ある (「だって眠いんだもん」); ものがある is register-neutral to formal and states a quality rather than excusing anything — もん never takes が, and ものがある never trails a petulant protest.
Both sit sentence-finally on the same もの／もん, and the か flips the speaker's stance — bare もん offers a petulant reason for what was done (知らなかったもん), while もんか rejects the proposition outright (知るもんか); one explains, the other refuses.