Japanese has two sentence styles: polite and plain. When each sentence in a conversation ends in a polite form (e.g., あした行きますか, おもしろいですね, 田中さんですよ), the conversation as a whole is considered polite. When sentences consistently end in a plain form (e.g., あした行く？, おもしろいね, 田中さんだよ), the conversation is considered plain.
Polite speech is used to maintain appropriate social distance—for example, with strangers, people you have just met, colleagues, acquaintances, students speaking to teachers, or subordinates speaking to superiors. Plain speech, by contrast, signals closeness and is used in informal, casual settings such as conversations with close friends, peers, or family members. Roughly speaking, using the plain form is like calling someone by their first name, while using the polite form is like saying “Mr.” or “Ms.” This distinction is often illustrated graphically: the vertical axis represents social hierarchy (higher–lower, older–younger), and the horizontal axis represents social distance (close–distant, in-group–out-group). Depending on whether you regard someone as part of your in-group (almost like family), you may or may not choose to use the plain form, even with a peer.
Deciding when to use the plain form is not easy. First, Japanese speakers tend to be highly sensitive to seniority and social ranking; even a one-year age difference can make people feel they are not truly “equal.” Second, permission to use the plain form is not necessarily mutual. For example, a senior colleague may feel justified in using the plain form while expecting a junior colleague to continue using polite forms. Third, in real interactions, speakers sometimes switch between polite and plain forms with the same person for pragmatic, emotional, or situational reasons. FYI: If you are a foreign visitor to Japan and fail to use polite forms where they are expected, this is often tolerated, as such lapses are attributed to limited experience with Japanese.
In Lesson 8, we introduced the plain forms. In casual speech among peers, friends, and family members, plain forms are commonly used. When the context is clear, certain particles—such as the object marker を and the topic marker はわ—may be omitted. The following outlines the general pattern for casual speech. The feminine sentence particle わ may be optionally added to a statement (わ is never used in questions). When the sentence particles よ (assertion) and ね (agreement) are present, わ precedes them. In casual speech, women may use both a blunt style and a softer, more gentle style, whereas men typically use only the blunt style. ( In casual speech, the copula だ is often omitted to create a neutral-sounding plain form.)
Table 1. Polite vs. Plain Forms
with Sentence Particles
Statements
Polite
Blunt
Plain
Feminine
Plain
polite-V
→plain-V
いきます
いきますよ
いきますね
いく
いくよ
いくね
いくわ
いくわよ
いくわね
い-Adjです →い-Adj
たかいです
たかいですよ
たかいですね
たかい
たかいよ
たかいね
たかいわ
たかいわよ
たかいわね
Noun
→Noun (だ)
(だ is often dropped
if nothing follows.)
先生です
先生ですよ
先生ですね
先生（だ）
先生だよ
先生だね
先生だわ
先生よ
先生ね
な-Adjです →な-Adj (だ)
(だ is often dropped
if nothing follows.)
きれいです
きれいですよ
きれいですね
きれい（だ）
きれいだよ
きれいだね
きれいだわ
きれいよ
きれいね
はい →うん
はい
うん ( )
いいえ →ううん/うううん
いいえ
ううん
( ) or
うううん ( )
Connective が →けど
が
けど
The explanation mode (Lesson 8) can be added to the casual pattern as shown below.
Table 2. Polite vs. Plain Forms
in Explanation Mode
Statements
Polite
Blunt-Plain
Feminine-Plain
plain-Vんです
→plain-Vんだ/の
いくんです
いくんですよ
いくんですね
いくんだ
いくんだよ
いくんだね
いくの
いくのよ
いくのね
い-Adjんです
→い-Adjんだ/の
たかいんです
たかいんですよ
たかいんですね
たかいんだ
たかいんだよ
たかいんだね
たかいの
たかいのよ
たかいのね
Nounなんです
→Nounなんだ/なの
先生なんです
先生なんですよ
先生なんですね
先生なんだ
先生なんだよ
先生なんだね
先生なの
先生なのよ
先生なのね
な-Adjなんです →な-Adjなんだ/なの
きれいなんです
きれいなんですよ
きれいなんですね
きれいなんだ
きれいなんだよ
きれいなんだね
きれいなの
きれいなのよ
きれいなのね
The question particle か is generally omitted in casual questions. Instead, questions are signaled by rising intonation, often accompanied by a slightly lengthened final vowel. In writing, however, this prosodic difference is difficult to represent, making it hard to distinguish a plain-form question from a plain-form statement. As a result, a question mark (?) is commonly used to indicate that a sentence is a question. In questions, the blunt–gentle style distinction largely disappears, and the feminine sentence particle わ is not used in casual questions.
Table 3. Polite vs. Plain Form Questions
Questions
Polite
Plain (Use "?".)
Polite-V →Plain-V?
いきますか
いく？
い-Adjです →い-Adj?
たかいですか
たかい？
Nounです →Noun?
先生ですか
先生？
な-Adjです →な-Adj?
きれいですか
きれい？
Really! I see.
[I accept it.]
そうですか
そうなんですか
そうでしたか
そうだったんですか
そうor そうか そうなの
そうだったの
Really? Is that so?
[I doubt it.]
そうですか
そうなんですか
そうでしたか
そうだったんですか
そう？
そうなの？
そうだった？
そうだったの？
Plain-Vんです → Plain-Vの?
いくんですか
いくの？
い-Adjんです → い-Adjの?
たかいんですか
たかいの？
Nounなんです → Nounなの?
先生なんですか
先生なの？
な-Adjなんです → な-Adjなの?
きれいなんですか
きれいなの？
⚠ Using the plain form with the question particle か (e.g., いくか, いくのか) is extremely blunt and, in most situations, sounds rude or confrontational. You should generally avoid this form. To ask a plain-form question, use the gentle style without か (e.g., いく？, いくの？). (そうか can be used as a form of self-directed speech meaning “Oh, I see!” rather than as a question to another person.) The following are common casual endings for negative expressions.
Table 4. Polite vs. Plain Negative Forms
Polite
Blunt-Plain
Feminine-Plain
いかないんです
いかないんですか
いかないんですよ
いかないんですね
いかないんだ
いかないの？
いかないんだよ
いかないんだね
いかないの
いかないの？
いかないのよ
いかないのね
よくないんです
よくないんですか
よくないんですよ
よくないんですね
よくないんだ
よくないの？
よくないんだよ
よくないんだね
よくないの
よくないの？
よくないのよ
よくないのね
きれいじゃないんです
きれいじゃないんですか
きれいじゃないんですよ
きれいじゃないんですね
きれいじゃないんだ
きれいじゃないの？
きれいじゃないんだよ
きれいじゃないんだね
きれいじゃないの
きれいじゃないの？
きれいじゃないのよ
きれいじゃないのね
先生じゃないんです
先生じゃないんですか
先生じゃないんですよ
先生じゃないんですね
先生じゃないんだ
先生じゃないの？
先生じゃないんだよ
先生じゃないんだね
先生じゃないの
先生じゃないの？
先生じゃないのよ
先生じゃないのね
The following are common issues:
●
Use of か in questions. (e.g., すき → すきか: Too rude)
●
Use of だ in questions. (e.g., すき？ →✽すきだか: Ungrammatical)
●
Use of わ in questions. (e.g., すき？ →✽すきわか: Ungrammatical)
●
Forgetting to use a question mark (？) in written questions. For example, いく can be interpreted as either a statement or a question, making it ambiguous in writing. Always use ？ to clearly mark a question.
🌸
Use of おれ: おれ is a very blunt first-person pronoun meaning “I.” It is typically used to project a strongly blunt, often masculine persona, and it sounds natural only when paired consistently with an equally blunt casual style. If used inconsistently, it can come across as awkward or unnatural. If you are still learning how to speak casually in Japanese, it is best to avoid using おれ.
The speaker's intention is expressed by the nonpast-plain-Vつもり（だ）: intend to V.
今日は、少し はやく帰る つもりです。
I to go home a little early.
あした、ともだちと うみに行く つもりです。
I intend to go to the beach with my friends tomorrow.
週まつ日本語をべんきょうする つもりです。
I intend to study Japanese during the weekend.
The negative form of つもり(だ) is either ないつもり(だ) or つもりはない. The latter (I have no intention to V whatsoever) expresses a stronger negative conviction of the speaker than the former (I intend not to V).
あの人には会わないつもりです。
I intend not to see him/her.
あの人に会う つもりは ありません。
I have no intention to see him/her.
パーティーには行かない つもりです。
I intend not to go to the party.
パーティーに行く つもりは ありません。
I have no intention to go to the party.
The word つもり can be modified by the demonstrative その.
A:
あした、来ますね。
You are coming tomorrow, right?
B:
ええ、そのつもりです。
Yes, I intend to. (Lit. It's that intention.)
The past tense of つもりだ is つもりでした, and it denotes what the speaker meant to do.
北海道
でゆきまつりを見るつもりでした。
I intended to see the Snow Festival in Hokkaido. [Implication: I didn't see it.]
イギリスからフランスへ行くつもりでした。
I intended to go to France from U.K. [Implication: I didn't go there.]
Both sentences refer to the same fact of Amy's losing her smartphone. Sentence (1) refers to the fact that happened in the past without any relevance to the present. All we know is that Amy lost it at some point in the past, and we don't know if she got it back. In Sentence (2), however, we know that Amy lost her smartphone and it is still missing. In Japanese, the same past tense form (Vました) can express both situations.
3.
エイミーさんはきのうハンバーガーを食べました。
Amy ate a hamburger yesterday.
4.
エイミーさんは もう ハンバーガーを食べました。
Amy has eaten a hamburger already.
Sentence (3) describes the simple past event of Amy's eating a hamburger yesterday disconnected from the present. Sentence (4), in contrast, describes Amy's eating hamburger that is still connected to the present (She is probably full now). The adverb もう (already) can be added to distinguish this difference. If you have not done something yet, this is stated in the resultant state form Vて(い)ません (have not V-ed). The simple past form (Vませんでした) cannot be used here. Speaker B below is expressing how she stands now (is still hungry) as the result of not eating. The adverb まだ (still) can be added to make this point clear. The abbreviated response まだです can also be used.
A:
もうハンバーガーを食べましたか。
Have you eaten the hamburger already?
B:
いいえ、まだ食べていません。 or いいえ、まだです。
(✽いいえ、まだ食べませんでした。)
No, I still haven't eaten it.
No, not yet.
[✽ Ungrammatical]
A:
もう田中さんから電話が来ましたか。
Has the phone call come from Mr. Tanaka already?
B:
いいえ、まだ来ていません。 or いいえ、まだです。
(✽いいえ、まだ来ませんでした。)
No, it still hasn't come.
No, not yet.
[✽Ungrammatical]
With the verb あります, the following exception applies:
A:
もう田中さんから電話がありましたか。
Have you already received a phone call from Tanaka?
The question particle か normally occurs at the end of a sentence. This particle can also occur between nouns and functions like the conjunction or --- ＡかＢ (A or B).
1.
あしたかあさって帰ります。
I will go home tomorrow or the day after tomorrow.
The particle で marks the means and tools by which one does something. The question word is
何
で (By means of what?). Don't confuse this with the particle で that marks the location of activity.
1.
[Means/Toolsで] A: スミスさんは 何で行きますか。 B:くるまで行きます。 (by means of a car)
2.
[Place of activityで] A: 田中さんはどこでべんきょうしますか。 B:としょかんでべんきょうします。(at the library)
To quote what someone said, we use ～と言って(い)ました (They said that...). The particle と is the quotation marker (that...). What's quoted is normally said in the plain form. In informal/casual conversation, the quotation marker と becomes って. Note also that the original tense is preserved in the quoted speech. Compare the underlined phrases in Japanese and English below.
1.
田中さんは あした学校に行かないと言って(い)ました。 Ms. Tanaka said that she would not go to school tomorrow.
2.
そのえいがは おもしろいって言って(い)たよ。 He said that the movie was interesting.
To state the speaker's thoughts, we use ～と思います (I think that...). The quoted thoughts must be in the plain form, and the original tense in quoted thoughts is preserved. The quotation particle と does not change to って in informal/casual conversation.
3.
まだきめていませんが、来年、日本に行くと思います。 I haven't decided yet, but I think I'm going to Japan next year.
4.
きのうは朝８時ごろ起きたと思います。 I think I woke up around eight o'clock in the morning yesterday.
5.
日本りょうりはおいしいと思います。 I think Japanese food is delicious.
6.
カラオケバーでうたをうたうのはたのしいと思うよ。 I think that singing songs at a Karaoke bar is fun.
To say that the speaker doesn't think something is the case, the Japanese use ～ないと思います more often than ～と(は)思いません.
7.
(私は)スミスさんは 田中さんがすきだと思います。 I think that Mr. Smith likes Ms. Tanaka.
8.
(私は)田中さんは スミスさんがすきじゃないと思います。 I don't think that Ms. Tanaka likes Mr. Smith.
(Lit. I think that Ms. Tanaka does not like Mr. Smith.)
Caution:
～と思います is an uncertainty expression. By adding と思います, you are implying that you are not 100% sure about something. If you are referring to your own direct experience such as your likes or dislikes, you normally don't use と思います with such expressions. Compare the following:
(私は)日本りょうりがすきだと思います。(I think I like Japanese food.)
[This is strange if you have already tasted Japanese food.]
This is more commonly said without 思います: 私は日本りょうりがすきです。
(私は)スミスさんは日本りょうりがすきだと思います。 (I think Mr. Smith likes Japanese food.)
[Acceptable because the speaker cannot have the direct experience of other people's likes and dislikes.]
The Vても pattern means even if V. When this pattern is combined with the adjective いい, it refers to an activity that is permitted: Even if ...., it is okay.
Table 5. Permission Form: Vてもいい
Vても
いい
その本を
読んでも
いいです。
It is okay even if you read that book. (=You may read that book.)
To ask for permission, we can use the question form ～てもいいですか (Is it okay to...? or May I...?).
A: これ、食べてもいいですか。 (Is it okay even if I eat this? = May I eat this?) B: ええ、どうぞ。 (Yes, go ahead.)
or ええ、
食べてもいいですよ。 (Yes, it is okay even if you eat it. = Yes, you may eat it.)
To deny the request for permission politely, use the following replies. こまる means to be inconvenienced.
A: これ、見てもいいですか。 B: すみませんが、ちょっと… or すみません。それはちょっとこまるんですが。 (I'm sorry. I would be a little inconvenienced [by that].)
To deny the request directly, use the ～ては いけません (You may not...).
A: これ、見てもいいですか。 B: いいえ、見てはいけません。 (No, you may not.)
Adjectives and nouns can also be changed into the ～ても forms as shown in Table 6.
Table 6. Adjective-ても/Noun-でも Forms
Plain Form
い-Adjくても
たかい
たかくても
even if it is expensive
な-Adjでも
だめだ
だめでも
even if it is no good
Nでも
あしただ
あしたでも
even if it is tomorrow
The following is a sample conversation between classmates using these grammar patterns. Before this conversation, B asked A, a student from the U.S., to make a short presentation for a promotional event. A is asking B about this.
A: 私のプレゼン、みじかくてもいい？ B: 何分なんぷんぐらい？
A: １分ぐらいなんだけど。
B: １分かあ…まあ、いいよ。
A: 英語でもいい？ B: 英語はちょっと…。日本語でおねがい。
A: Is it okay for my presentation to be short? B: How many minutes?
In casual speech, the copula 
)
) or
