The plain form (casual style)
たべます → たべる／たべない／たべた／たべなかった
Plain = dictionary form (食べる), ない, た, なかった. Same meaning as ます, used among close people and inside sentences.
In short
Among friends, you don't use ます but the plain form: the dictionary form (たべる), the negative (たべない), the past (たべた) and the past negative (たべなかった). です becomes だ: 学生だ. The plain form is also used to build complex sentences (～とき, ～まえに…).
- あした 行く？——うん、行く。ashita iku? — un, ikuAre you coming tomorrow? — Yeah, I'm coming.
- きのう えいがを 見た。kinō eiga o mitaI saw a film yesterday.
- 今日は 休みだ。kyō wa yasumi daToday is a day off.
Two registers: polite and plain
Until now, all the verbs were in the polite form (ます). Japanese also has a plain form, called the “dictionary form”: 食べる, 行く, する. It's the one used among friends and family, in newspapers, and above all inside sentences, before とき, まえに, でしょう, から…
The meaning is exactly the same; only the register changes. 食べます = 食べる, politely.
The four plain forms
Each polite form has its plain equivalent.
| Polite | Plain | Meaning |
|---|---|---|
| 食べます | 食べる | I eat |
| 食べません | 食べない | I don't eat |
| 食べました | 食べた | I ate |
| 食べませんでした | 食べなかった | I didn't eat |
Finding the dictionary form
Group 2: replace ます with る (食べます → 食べる). Group 1: the “i” syllable before ます becomes “u” (書きます → 書く, 飲みます → 飲む, 買います → 買う). Group 3: します → する, 来ます → くる.
| Group | ます | Dictionary |
|---|---|---|
| 1 | 書きます・飲みます・買います | 書く・飲む・買う |
| 2 | 食べます・見ます | 食べる・見る |
| 3 | します・来ます | する・くる |
The plain past: like the て-form
The た-form is built exactly like the て-form, replacing て with た (and で with だ): 書いて → 書いた, 飲んで → 飲んだ, 行って → 行った.
- きのう えいがを 見た。kinō eiga o mitaI saw a film yesterday. (among friends)
- あした 学校へ 行く？ashita gakkō e iku?Are you going to school tomorrow? (among friends)
Nouns and adjectives in the plain form
です becomes だ (or disappears in speech): 学生だ, しずかだ. い-adjectives simply drop です: たかい, たかかった. In a casual question, you just raise your intonation, without か.
Common mistakes
- Speaking in the plain form to a stranger or a superior: it's rude, keep ます.
- Adding か in casual style: “行くか” sounds curt, you say 行く？ with a rising intonation.
- Forgetting the exceptions: ある → ない (not あらない), 行く → 行った.
5 exercises on this point
Particles to choose, sentences to put back in order, translations: marked straight away, then reviewed at the right time. This JLPT N5 point is on the Chūō Line (The plain form) of the Tokyo subway.