ものだから details
write + because — offered as an excuse the speaker could not help
kaku mono da kara
because — offered as an excuse the speaker could not help
バスが全然来なかったもんだから、遅れちゃった。ごめん。
basu ga zenzen konakatta mon da kara, okurechatta. gomen.
The bus just wouldn't come, so I ended up late. Sorry. casual
あまりに眠かったものだから、話の途中で寝てしまいました。
amari ni nemukatta mono da kara, hanashi no tochuu de nete shimaimashita.
I was just so sleepy that I fell asleep in the middle of the talk. neutral
- dictionary form
- i-adjective
- na-adjective
- noun
- colloquial
- alternant
- polite
Examples
because — the speaker explains an act or lapse by a cause outside their control, expecting to be excused
バスが全然来なかったもんだから、遅れちゃった。ごめん。
basu ga zenzen konakatta mon da kara, okurechatta. gomen.
The bus just wouldn't come, so I ended up late. Sorry. casual
あまりに眠かったものだから、話の途中で寝てしまいました。
amari ni nemukatta mono da kara, hanashi no tochuu de nete shimaimashita.
I was just so sleepy that I fell asleep in the middle of the talk. neutral
不慣れなものですから、お時間をいただいてしまい申し訳ございません。
funare na mono desu kara, o jikan o itadaite shimai moushiwake gozaimasen.
I am new to this, so I am sorry to have taken up your time. formal
Formation
{V}ものだからattaches to dictionary formplain clause + ものだからattaches to plain clause{I}ものだからattaches to i-adjective{NA-stem}なものだからattaches to na-adjective{N}なものだからattaches to noun
Variant notes
- もんだから — the spoken squeeze — 眠かったもんだから寝ちゃった. Speech and messaging only.
- もので — the で shape is the softer form and dominates in polite apology — 不慣れなもので、お待たせしました.
Notes
invitation cannot follow ものだから, where ので takes all three. The もので
alternant does front set requests — 不慣れなもので、よろしくお願いします.
Related patterns
Similar
ので offers a reason as plain circumstance and takes a request or an instruction after it freely (寒いので、窓を閉めてください); ものだから claims the cause left the speaker no choice, so its main clause is something already done that is now being accounted for — ×寒いものだから、窓を閉めてください does not stand.
せいで points outward and assigns fault for an unwanted outcome whoever it befalls (雨のせいで中止になった); ものだから is the speaker's own defence of the speaker's own act, so its main clause names what the speaker did — せいで in an apology accuses the cause, ものだから asks to be let off.
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.
ものだから pleads a cause outside the speaker's control and asks to be let off; ばかりに asks for nothing and only registers that the price ran far past what caused it — which is why ばかりに takes a third party's misstep as readily as the speaker's own (彼が嘘をついたばかりに、みんなが迷惑した), while ものだから is always the speaker's own defence.
Lookalikes
The same もの head, and neither is the other's clause form — ものだ states a general truth about how things are as a rule (人は間違えるものだ), while ものだから's もの carries no truth claim at all and only props up one lapse (間違えたものだから、やり直しました); adding だから to a ものだ sentence turns a norm into an excuse.
One nominal head apart and constantly swapped, but they run in opposite directions in time — ことだから grounds a PREDICTION in a known party's character (彼のことだから、また遅れるだろう) and its main clause is conjectural, while ものだから excuses something ALREADY done by a cause the speaker did not control (寝坊したものだから、遅れました); ×彼のことだから遅れました excuses nothing.
ものだから packages a finite clause as an excuse for something already done and always needs an antecedent clause before it (電車が遅れたものだから、遅刻した); ものがある is not a connective — it attaches directly to the one adjective or clause it describes and needs nothing to follow.
Both wedge もの between two clauses, and the connective they carry is opposite — ものの concedes the first clause and denies what it would lead you to expect, while ものだから offers the first clause as the CAUSE of the second; swap them and the sentence's logic reverses, which the shared もの hides at reading speed.