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JLPT N2Cause & Effect

～もの／もん— Because, You See

Sentence-final もの (casually もん) gives an emotional, somewhat childish or coquettish justification for what was just said. It softly insists 'because…, that's why' and appeals for understanding or makes an excuse. It is common in casual conversation, especially among women and children.

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Pro lessonUNIT 55 · CAUSE & EFFECT

Structure · 形

[Plain form] + もの／もん (often だって…もの)

Examples · 例文

  • 行きたくない。だって疲れているんだもの。

    Ikitakunai. Datte tsukarete iru n da mono.

    I don't want to go — because I'm tired, that's why.

    もの gives an emotional excuse, often paired with だって at the front.

  • だってお腹が空いたんだもん。

    Datte onaka ga suita n da mon.

    But I'm hungry, you know!

    もん (casual もの) makes a childish, pleading justification.

  • できないよ、まだ習っていないもの。

    Dekinai yo, mada naratte inai mono.

    I can't do it — I haven't learned it yet, that's why.

    もの justifies the inability with an appeal for understanding.

Usage notes · 注意

  • もん is the more casual, spoken form of もの.
  • Often introduced by だって for a defensive/excusing tone.
  • Register: casual conversation; sounds childish or endearing, avoid in formal settings.

Commonly confused with

The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ～もの／もん is tested against.

vs～から／～ので

から/ので state reasons neutrally, while もの adds an emotional, excusing, appealing-for-sympathy nuance.

vs～ものだから

ものだから gives a reason mid-sentence as an explanation/excuse, whereas sentence-final もの is a short emotional justification tacked on at the end.

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