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Plain formN52 rules

Plain form (普通形) and when to use it instead of です・ます

Plain form is the casual register — and, just as importantly, the form that subordinate clauses require regardless of how polite the sentence ends. These cards cover both the conjugation table and the choice of register.

Also known asplain form普通形futsuukeicasual formplain vs polite

Plain & polite forms

How the same thing looks in the polite (丁寧形) and plain (普通形) style — for verbs, adjectives and nouns.

Form丁寧形Polite普通形Plain
Verb (行く) — go
non-past +
non-past −
past +
past −
い-adjective (高い) — expensive
non-past +
non-past −
past +
past −
な-adjective (元気) — well / fine
non-past +
non-past −
past +
past −
Noun (学生) — student
non-past +
non-past −
past +
past −
1
Plain form (普通形)Plain (casual) style
Plain form

ます → dictionary/ない/た forms; です → だ. Used with close people.

あした　京都へ　行く。

あした　きょうとへ　いく。

I'm going to Kyoto tomorrow. (casual)

Plain style swaps the polite endings for plain ones: 行きます→行く, 行きません→行かない, 行きました→行った. It is used with family and close friends; the polite ます-style stays for everyone else.

In the textbooksMinna I, lesson 20Genki I, lesson 8

2
N / な-adj だです → だ (plain)
Plain form

In plain style, です becomes だ (often dropped in casual speech).

これ、わたしの　本だ。

これ、わたしの　ほんだ。

This is my book. (casual)

Nouns and な-adjectives use だ as the plain copula (past だった). In casual conversation だ is often omitted, especially by women: これ、わたしの 本.

  • Casual yes/no questions drop か and just rise in intonation: ごはん 食べる？

In the textbooksMinna I, lesson 20Genki I, lesson 8