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JLPT N4Sentence Ending Particles

かい— Really? / Is that so? (masculine casual)

A casual question particle primarily used by male speakers. Softer than か alone; shows curiosity, mild surprise, or seeks casual confirmation.

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Pro lessonUNIT 22 · SENTENCE ENDING PARTICLES

Structure · 形

[Plain form] + かい / [Noun / な-adj + な] + のかい

Examples · 例文

  • 本当に行くのかい？

    Hontou ni iku no kai?

    Are you really going?

    行く (plain) + のかい = mild surprise + seeking confirmation

  • もう帰るのかい、早いね。

    Mou kaeru no kai, hayai ne.

    Are you leaving already? That's early.

    帰る + のかい = surprised comment

  • 大丈夫かい？

    Daijoubu kai?

    Are you alright?

    大丈夫 (na-adj) + かい = casual concerned question

Usage notes · 注意

  • Key Concept: かい is primarily masculine and casual.
  • Question: Women typically use の？or かな.
  • Detail: Inappropriate in formal settings.
  • Detail: Often heard from fathers, older men, or mentor figures.

Commonly confused with

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

vsか (plain question particle)

Plain か can sound blunt or interrogative; かい softens it into a warm, curious, distinctly masculine-casual question.

vsだい (question-word question ending)

だい pairs with question words (何だい, どこだい = 'what is it?', 'where?'); かい is for yes/no questions (行くのかい = 'are you going?').

vsかな (self-wondering)

かい is addressed TO a listener seeking their answer; かな is you musing to yourself, not really expecting a reply.

More sentence ending particles

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