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JLPT N5Adjectives

い-Adjectives(i-adj) — True Conjugating Adjectives

A distinct class of adjectives ending in the hiragana い. They behave more like verbs than nouns because they conjugate themselves for tense and negation without relying on the copula.

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Free lessonUNIT 4 · ADJECTIVES

Structure · 形

[い-Adj] + Noun | [い-Adj] + です

Examples · 例文

  • 面白い映画を見ました。

    Omoshiroi eiga o mimashita.

    I watched an interesting movie.

    面白い (interesting) directly modifies 映画 (movie), no particle needed

  • 今日は寒くないです。

    Kyou wa samukunai desu.

    It is not cold today.

    寒い → 寒くない (negative: drop い, add くない)

  • テストは難しかったです。

    Tesuto wa muzukashikatta desu.

    The test was difficult.

    難しい → 難しかった (past: drop い, add かった)

Usage notes · 注意

  • Conjugation: Keep the stem, swap the ending. Negative = くない, Past = かった, Past negative = くなかった.
  • Irregular いい: 'Good', いい (ii), is irregular because its stem is よい (yoi): 'not good' = よくない, 'was good' = よかった.
  • Modification: Never insert な or の when placing an い-adjective before a noun (面白い映画, not 面白いな映画).

Commonly confused with

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

vsな-adjectives

い-adjectives conjugate themselves (寒い→寒くない→寒かった) and attach directly to nouns; な-adjectives don't conjugate — the copula does the work (元気だ→元気じゃない), and they need な before a noun (元気な人).

vsな-adjectives that end in い (綺麗, 嫌い)

A few な-adjectives end in the sound い (きれい, きらい) but are NOT い-adjectives: they take な (綺麗な人) and conjugate via the copula (綺麗じゃない), never 綺麗くない.

More adjectives

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