ConjugationBeginner5 min read

Japanese Dictionary Form: The Base of All Conjugations

辞書形

Learn the dictionary form (辞書形) - the basic form of Japanese verbs and adjectives found in dictionaries. Essential foundation for all conjugations.

The dictionary form (辞書形 - jisho-kei) is the basic, unconjugated form of verbs and adjectives. It's called the "dictionary form" because this is how words appear in Japanese dictionaries. Understanding this form is essential as it's the starting point for all other conjugations.

What is the Dictionary Form?(辞書形とは)

The dictionary form is the plain, present-affirmative form of a word. For verbs, it always ends in an う-sound:

  • Godan verbs: End in う, く, ぐ, す, つ, ぬ, ぶ, む, る
  • Ichidan verbs: End in いる or える
  • Irregular: する and くる

For adjectives:

  • い-adjectives: End in い (高い, 新しい)
  • な-adjectives: Base form without な (静か, 元気)

Identifying Verb Types(動詞の種類)

From the dictionary form, you can identify the verb type:

EndingTypeExamples
〜う, 〜く, 〜す, etc.Godan買う, 書く, 話す
〜いる, 〜えるUsually Ichidan食べる, 見る, 起きる
するIrregularする, 勉強する
くるIrregularくる, 持ってくる
!

Some verbs ending in -iru/-eru are actually godan (like 走る, 帰る). These exceptions must be memorized.

When to Use Dictionary Form(辞書形の使い方)

The dictionary form is used in:

  • Casual speech: With friends and family
  • Before certain grammar: ことができる, と思う, etc.
  • Modifying nouns: 食べる人 (person who eats)
  • Quotes: 「行く」と言った (said "go")
明日、映画を見ると思う。
あした、えいがをみるとおもう。
ashita, eiga wo miru to omou.
I think I'll watch a movie tomorrow.

Summary

The dictionary form is your foundation:

  • All verbs end in う-sound
  • Used in casual speech and before grammar patterns
  • Essential for identifying verb types

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