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JLPT N5Adjectives

い-Adjective Conjugation Core

い-adjectives carry their own tense and negation (like verbs). You conjugate by dropping the final い and adding the ending — no だ/です needed to be grammatical.

Grammar path · 練習

Practice this in the path

A short lesson: the pattern, its sentence anatomy, a quick quiz and a sentence to build.

Pro lessonUNIT 17 · ADJECTIVES

Structure · 形

Stem (drop い) + い (present) / くない (negative) / かった (past) / くなかった (past negative)

Examples · 例文

  • 暑い → 暑くない / 暑かった / 暑くなかった

    atsui → atsukunai / atsukatta / atsukunakatta

    hot → not hot / was hot / was not hot

    Each form drops the final い and adds the ending (くない / かった / くなかった)

  • いい → よくない / よかった / よくなかった

    ii → yokunai / yokatta / yokunakatta

    good → not good / was good / was not good

    Irregular: いい comes from よい, so every conjugated form uses the よ- stem

  • 寒い → 寒くない / 寒かった / 寒くなかった

    samui → samukunai / samukatta / samukunakatta

    cold → not cold / was cold / was not cold

    Regular pattern: drop the final い and add くない / かった / くなかった

Usage notes · 注意

  • い-adjectives don't need だ/です to be grammatical: 寒い。('It's cold.') is a complete sentence. Adding です (寒いです) just makes it polite — you never say 寒いだ. • Irregular いい/よい is the one to memorise.

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-Adjective is tested against.

vsな-adjectives

い-adjectives conjugate themselves (暑かった); な-adjectives don't — they rely entirely on the copula (静かだった) and need な before a noun.

More adjectives

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