Lesson 14
1. Top
2. Kanji in Lesson 14
3. たんご
4. 会話
5. ぶんぽう
1. Plain Form + んです
2. …すぎる: Too Much/ ...
3. …でしょう: Probably...
4. Vたほうがいい (You ...
5. Must V; Have to V
6. Vてはいけない
7. Vないでください
8. しる vs. しっている
6. れんしゅう
1

Plain Form + んです (Review)

We learned the explanatory mode of speech …んです in Lesson 8. …んです is the conversational form of the more formal …のです. We also learned that questions with どうして (“why?”) normally use …んですか:
  • どうして行かないんですか。 Why aren't you going?

However, …んです can also be used without どうして. It is often used when the speaker connects what they are saying to the situation or context—for example, something the speaker has just seen, heard, or noticed. Imagine that it is 5:00 p.m. Your coworker gets up from her chair, gathers her belongings, puts on her coat, and starts toward the door. You could simply ask Sentence (1), but Sentence (2a) is more natural because your question is prompted by what you have just observed.

  1. かえりますか。　Are you leaving? (A simple question: I am just asking whether you are leaving.)
  2. かえるんですか。　Oh, are you leaving?rising intonation (I see what you are doing, and I am asking whether you are leaving.)

With falling intonation, the same form can instead be a statement expressing a realization:

  1. かえるんですか。　Oh, you're leaving. / So you're leaving.falling intonation

    (Now I understand the situation.)

Thus, …んですか does not necessarily make a sentence a question. In conversation, intonation and context determine whether the speaker is asking a question or expressing a realization.

Forms before …んです

…んです generally follows the plain form. However, with non-past affirmative nouns and な-adjectives, だ changes to な before …んです:
Non-Past
かえるんです。
 It's that (someone) is going home.
かえらないんです。
 It's that (someone) is not going home.
たかいんです。
 It's that it is expensive.
たかくないんです。
 it's that it is not expensive.
ひまなんです。
 It's that I'm free.
ひまじゃないんです。
 It's that I'm not free.
日曜日なんです。
 It's that it's Sunday.
日曜日じゃないんです。 It's that it's not Sunday.
Past
かえったんです。
 It's that (someone) went home.
かえらなかったんです。
 It's that (someone) did not go home.
たかかったんです。
 It's that it was expensive.
たかくなかったんです。
 It's that it was not expensive.
ひまだったんです。
 It's that I was free.
ひまじゃなかったんです。
 It's that I was not free.
日曜日だったんです。
 It's that it was Sunday.
日曜日じゃなかったんです。 It's that it was not Sunday.

Notice that the past tense is expressed by the word before ～んです:

  • かえるんです → かえったんです
  • ひまなんです → ひまだったんです

Do not change ～んです itself to ～んでした to express the past.

Plain Speech

In plain speech, ～んです corresponds to ～の or ～んだ:
  • A: どうして行かないの？ Why aren't you going?
  • B: 今日は行かないんだ。 I'm not going today. / The thing is, I'm not going today.
Sentence-final ～の generally sounds gentler, while ～んだ is more assertive and can sound blunt depending on the situation.
2

…すぎる: Too Much/Too ...

The verb すぎる (“to exceed; to go beyond”) can be attached to a verb or an adjective to express the idea of “too much” or “too ...”. The resulting expression functions as a る-verb and conjugates like other る-verbs (e.g., ～すぎます, ～すぎました, ～すぎない). With verbs, attach すぎる to the verb stem (the ます-form without ます):

Stem + すぎる Examples  
のみます ＋すぎる おさけを飲みすぎました。 I drank too much.
みます ＋すぎる テレビを見すぎました。 I watched too much TV.
勉強(べんきょう) します ＋すぎる きのう勉強しすぎた。 I studied too much yesterday.　

With い-adjectives, drop the final い and add すぎる:

Stem + すぎる Examples  
たかい ＋すぎる あの車は高すぎます。 That car is too expensive.
うるさい ＋すぎる テレビがうるさすぎます。 The TV is too loud.
むずかしい ＋すぎる このテストはむずかしすぎた。 This test was too difficult.
やすい ＋すぎる 私のきゅうりょうは安すぎる。 My salary is too low.

With な-adjectives, attach すぎる directly to the adjective stem (without な):

Stem + すぎる Examples  
にぎやかな ＋すぎる ここはにぎやかすぎる。 This place is too lively.
しずかな ＋すぎる そのクラスはしずかすぎる。 That class is too quiet.
げんきな ＋すぎる あの子は元気すぎる。 That child is too energetic.
すぎる does not normally attach directly to nouns:
  • ✽びょうき　＋ すぎる　[Ungrammatical as a regular N + すぎる combination]

V-stem + すぎる and V-stem + たい

Notice that both ～すぎる and ～たい attach to the same verb stem:
Stem + すぎる Stem + たい
およぎすぎる to swim too much およぎたいto want to swim
つくりすぎる to make too much つくりたい to want to make
食べすぎる to eat too much 食べたい to want to eat

Negative Forms + すぎる

Some negative forms can also be combined with すぎる. In this pattern, the final い of …ない is replaced by さ, giving ～なさすぎる:
Neg. + すぎる Example
食べないさすぎる その子はごはんを食べなさすぎる。 That child eats too little.
勉強しないさすぎる 勉強しなさすぎる。 She studies too little.
おもしろくないさすぎる この本はおもしろくなさすぎる。 This book is not interesting enough.
べんりじゃないさすぎる べんりじゃなさすぎた。 It was much too inconvenient.
The meaning of …なさすぎる is often naturally expressed in English as “not ... enough” or “too little.” Note: This negative pattern is more restricted, and not every negative expression is naturally used with …すぎる. Finally, the V-stem + すぎる pattern is unrelated to the Vて-form connection introduced earlier. …すぎる attaches directly to the verb stem, not to the て-form.
3

…でしょう: Probably; I wonder

When we are not completely certain that something is true, we can use …でしょう to express a prediction or conjecture. It often corresponds to English “probably,” “I think ...,” or “I guess ....” The plain form of でしょう is だろう. Compare:

  • あしたは雨です。 It will rain tomorrow.
  • あしたは雨でしょう。 It will probably rain tomorrow.

The first sentence presents the information simply as a statement. The second presents it as the speaker's prediction or conjecture.

Plain Form + でしょう

でしょう can follow verbs and adjectives as well as nouns. The predicate before でしょう is generally in the plain form.
  • 田中さんはあした来るでしょう。 Ms. Tanaka will probably come tomorrow.
  • 田中さんはあした来ないでしょう。 Ms. Tanaka probably won't come tomorrow.
Although the form before でしょう is a plain form, a sentence ending in でしょう is polite.

～でしょうか: I wonder ...

When でしょう is turned into a question, ～でしょうか expresses uncertainty and invites the listener's opinion. It can often be translated as “I wonder if ...” or “Do you think ...?”

  • Q: 田中さんは来るでしょうか。 　　I wonder if Ms. Tanaka will come.
  • A: （たぶん）来ないでしょう。 　　She probably won't come.
The adverb たぶん (“probably”) is often used with でしょう, but it is optional.　The same pattern can be used with い-adjectives:
  • Q: あのえいがはおもしろいでしょうか。 　　I wonder if that movie is interesting.
  • A: （たぶん）おもしろくないでしょう。 　　It's probably not interesting.

な-Adjectives and Nouns

With non-past affirmative な-adjectives and nouns, do not use だ before でしょう:
  • すきだ → すきでしょう
  • 田中さんの車だ → 田中さんの車でしょう
Compare:
  • Q: 田中先生はコーヒーがすきでしょうか。 　　I wonder if Prof. Tanaka likes coffee.
  • A: （たぶん）すきじゃないでしょう。 　　He probably doesn't like it.
  • Q: あれは田中さんの車でしょうか。 　　I wonder if that is Mr. Tanaka's car.
  • A: （たぶん）そうじゃないでしょう。 　　It probably isn't.
Notice that the negative forms retain the plain-form ending:
  • すきじゃない + でしょう → すきじゃないでしょう
  • 車じゃない + でしょう → 車じゃないでしょう

でしょう？ / でしょ？: ... right?

In conversation, でしょう？ can also be used with rising intonation when the speaker expects the listener to agree. It is often similar to “... right?” or “... isn't it?” in English. In casual conversation, でしょう is frequently shortened to でしょ.
  • 今、9時でしょう？　It's 9 o'clock, right?
  • 今、9時でしょ？　 It's 9 o'clock, right?
This use is somewhat different from the “probably” meaning of でしょう: rather than simply making a prediction, the speaker is seeking confirmation or agreement.

だろう and ～だろうと思います

The plain form of でしょう is だろう.
  • でしょう → polite
  • だろう → plain
A stand-alone statement ending in だろう can sound quite assertive or blunt depending on the context, so beginning students should be cautious about using it in conversation.　However, だろう is commonly used before と思います:
  • あしたは雨がふるでしょう。 It will probably rain tomorrow.
  • あしたは雨がふるだろうと思います。 I think it will probably rain tomorrow.
In ～だろうと思います, だろう expresses the speaker's tentative prediction, while と思います makes the overall sentence polite. This combination is useful when the speaker wants to present a prediction or judgment cautiously.
4

Vたほうがいい (You should V)

When giving advice or a recommendation, Japanese often uses the comparative pattern ～ほうがいい. Literally, this pattern means that one choice or course of action is “better” than another. In an affirmative recommendation, the verb before ほう is typically in the plain past form (Vた):

Modifying Clause Nが いい
Vた ほうが いい
Thus, Vたほうがいい literally means “Doing V is the better choice” and is usually translated as “You should V” or “You had better V.”
  • はやくおきたほうがいいです。 　You should get up early.
  • 毎日、れんしゅうしたほうがいいです。 　You should practice every day.
  • シャワーをあびたほうがいいですよ。　 You should take a shower.
  • おふろにはいったほうがいいですよ。 　You should take a bath.

Notice that although Vた is a past form, Vたほうがいい does not normally refer to a past action. The Vた form is part of this grammatical pattern for giving advice.　The structure also contains a modifying clause: Vた modifies the noun ほう (“side; alternative; choice”).

Vないほうがいい: You should not V

To recommend not doing something, use Vないほうがいい. In this case, the verb is in the plain non-past negative form (Vない):
Modifying Clause Nが いい
Vない ほうが いい
Vないほうがいい literally means “Not doing V is the better choice” and is usually translated as “You should not V” or “You had better not V.”
  • コンピュータをつかわないほうがいいです。 You should not use a computer.
  • じしょを見ないほうがいいですよ。 You should not look at a dictionary.
  • シャワーをあびないほうがいいですよ。 You should not take a shower.
  • おふろにはいらないほうがいいですよ。 You should not take a bath.
Compare the two patterns:
  • Vたほうがいい → You should do V.
  • Vないほうがいい → You should not do V.
  • はやくねたほうがいいですよ。 You should go to bed early.
  • あまりおそくまでおきていないほうがいいですよ。 You shouldn't stay up too late.
5

Must V; Have to V
To say that someone must do or has to do something, Japanese commonly uses Vなくてはいけません or Vなければなりません. These expressions are based on a double-negative idea. For example:
  • 行かなくてはいけません。
can be understood literally as:
  • 行かなくては　if (someone) does not go 　　＋
  • いけません　it is not okay
In other words, “Not going is not okay” → “You must go.” Similarly:
  • 行かなければなりません。 If (someone) does not go, it will not do. → Someone must go.

In English, these patterns are usually translated simply as “must” or “have to.”

Basic Forms

Start with the plain negative Vない form. Replace the final ない with なければ or なくては, and add ならない／なりません or いけない／いけません.
Plain Negative Obligation
食べない 食べなければならない 食べなくてはいけない
飲まない 飲まなければならない 飲まなくてはいけない
行かない 行かなければならない 行かなくてはいけない
来(こ)ない 来なければならない 来なくてはいけない
しない しなければならない しなくてはいけない
All of these express the meaning “(someone) must/has to V.” The polite forms end in なりません／いけません:
  • 食べなければなりません。 You have to eat it.
  • 食べなくてはいけません。 You have to eat it.
…なければなりません tends to sound somewhat more formal or written, while ～なくてはいけません is also very common in everyday speech.

Contracted Forms in Conversation

In casual conversation, these expressions are frequently contracted:
  • ～なければ → ～なきゃ
  • ～なくては → ～なくちゃ
Plain Negative Contracted Form
食べない

食べなきゃ 食べなくちゃ
飲まない 飲まなきゃ 飲まなくちゃ
行かない 行かなきゃ 行かなくちゃ
来(こ)ない 来なきゃ 来なくちゃ
しない しなきゃ しなくちゃ

The contracted forms can still be followed by ならない／いけない:

  • 明日の朝は７時に起(お)きなくちゃいけない。
  • 明日の朝は７時に起きなきゃいけない。 I have to get up at 7:00 tomorrow morning.

Past Obligations

To express a past obligation (“had to”), change the final expression to the past tense:
  • 日本語で話さなくてはいけませんでした。
  • 日本語で話さなければなりませんでした。
    I had to speak in Japanese.
  • シンデレラは夜の12時までに家に帰らなくてはいけなかった。
  • シンデレラは夜の12時までに家に帰らなければならなかった。 Cinderella had to go home by midnight.
Notice that the first part (～なくては／～なければ) does not change. The tense is expressed by the final いけない／ならない.

～なくちゃだめ

The final いけない／ならない can also be replaced by another expression meaning “not good,” such as だめ:
  • この薬を( くすり )飲まなくちゃだめよ。 You have to take this medicine.
This is common in conversation.

Dropping いけない／ならない

In casual conversation, the final いけない／ならない is often omitted entirely. The shortened ～なきゃ or ～なくちゃ alone can express the obligation:
  • もう少し練習(れんしゅう)しなきゃ。 I/You have to practice a little more.
  • もう行かなくちゃ。 I have to go now.
Because Japanese often omits the subject, the person who has to do something is determined from context.
6

Vてはいけない: must not V
We have just learned Vなくてはいけない (“must/have to V”). If the first negative なくて is replaced with the affirmative Vて-form, we get Vてはいけない, which expresses prohibition:
  • Vなくてはいけない: You must V.
  • Vてはいけない: You must not V.
The literal idea behind Vてはいけない is “If you V, it is not okay.” This pattern was introduced in Lesson 12 in connection with the permission pattern Vてもいいですか (“May I V?”).
  • A: これ、見てもいいですか。　　 Is it okay if I see this? / May I see this?
  • B: いいえ、見てはいけません。　　 No, you may not see it. / You must not see it.
Compare:
  • Vてもいい　　It is okay to V. → You may V.
  • Vてはいけない　　It is not okay to V. → You must not V.

Casual Forms: ～ちゃいけない／～ちゃだめ

In casual conversation, ては can be contracted to ちゃ:
  • Vてはいけない → Vちゃいけない
  • A: これ、見てもいい？　　May I see this?
  • B: ううん、見ちゃいけない。　　No, you can't.
The final いけない can also be replaced by だめ:
  • A: これ、食べてもいい？ May I eat this?
  • B: あ、食べちゃだめよ！ Oh, you can't eat that!

Vなくてもいい: do not have to V

We can also use the negative て-form (Vなくて) with ～もいい:
  • Vなくてもいい
  • It is okay even if you don't V. → You don't have to V.
Compare this with Vなくてはいけない:
  • Vなくてもいい　　It is okay not to V. → You don't have to V.
  • Vなくてはいけない　　It is not okay not to V. → You must V.
For example:
  • A: これ、読まなくてもいいですか。　Is it okay if I don't read this? / Do I have to read this?
  • B: いいえ、読まなくてはいけません。　No, you have to read it.

Comparing the Four Patterns

The combination of Vて / Vなくて and もいい / はいけない produces four related meanings:
  …てもいい“it is okay” …てはいけない “it is not okay”
Vて VてもいいYou may V. Vてはいけない You must not V.
Vなくて VなくてもいいYou don't have to V. VなくてはいけないYou must V.
Notice how the meanings follow logically from whether doing V or not doing V is okay.

How Would You Answer “No”?

Compare the following four questions. Click on each arrow to reveal the answer. Notice what a negative answer (いいえ) means in each case.
  1. A: 行ってもいいですか。 　Is it okay if I go? / May I go?
    B: いいえ、⇒
  2. A: 行かなくてもいいですか。　　Is it okay if I don't go? / Do I have to go? B: いいえ、⇒
  3. A: 行ってはいけませんか。　　Is it not okay if I go? / Am I not allowed to go? B: いいえ、⇒
  4. A: 行かなくてはいけませんか。　　 Is it not okay if I don't go? / Must I go? B: いいえ、⇒
The last two questions contain a negative expression (…てはいけませんか), so be especially careful with はい／いいえ. Rather than translating はい and いいえ mechanically as “yes” and “no,” pay attention to what the speaker is confirming or denying.
7

Vないでください: Please don't V
The Vないでください pattern is used to make a request not to do something. It corresponds to English “Please don't V.” It can be thought of as the negative counterpart of Vてください (“Please V”).
  • 行ってください。　　Please go.
  • 行かないでください。　　Please don't go.
To form this pattern, add でください to the plain negative Vない form. In casual conversation, ください can be omitted.
Vない でください
食べない でください Please don't eat it. A woman is leaving a man. A man is saying "Please don't go..."
飲まない でください Please don't drink it.
しない でください Please don't do it.
行かない で Don't go. [Casual]

Practice: Change the following Vてください to Vないでください.

  1. 見てください。⇒
  2. 言ってください。⇒
  3. 来(き)てください。⇒
  4. つくってください。⇒
  5. およいでください。⇒
  6. 話してください。⇒
  7. 使(つか)ってください。⇒
  8. 書(か)いてください。⇒
  9. まってください。⇒

Vてはいけません vs. Vないでください

We have learned that Vてはいけません expresses a prohibition: “You must not V / You may not V.” A similar idea can often be expressed as a request using Vないでください:
  1. 部屋(へや)に入(はい) ってはいけません。　　You must not enter the room. ⇒ 部屋(へや)に入らないでください。　　Please don't enter the room.
  2. ここでたばこをすってはいけません。　　You must not smoke here. ⇒　ここでたばこをすわないでください。　　Please don't smoke here.
  3. クラスでスマホをつかってはいけません。 　You must not use the smartphone in class. ⇒ クラスでスマホをつかわないでください。　　Please don't use the smartphone in class.

In casual speech:

  1. テレビを見ちゃいけない。　You can't watch TV. ⇒ テレビを見ないで。　　Don't watch TV.
Although the two patterns can be used in similar situations, their functions are different:
  • Vてはいけません → states that an action is not allowed
  • Vないでください → asks someone not to do an action

Responding to Vてもいいですか

Vないでください can also be used when responding negatively to a request for permission:
  • ここで食べ物を食べてもいいですか。 May I eat food here? → いいえ、食べないでください。 No, please don't.
  • ChatGPTをつかってもいいですか。 May I use ChatGPT? → いいえ、つかわないでください。 No, please don't.
  • 図書館で音楽を聞いてもいいですか。 May I listen to music in the library? → いいえ、聞かないでください。 No, please don't.
In casual conversation:
  • キックボードにのってもいい？　　Can I ride the kick scooter? → ううん、のらないで。　　No, don't.
More direct response is:
  • → ううん、だめ。　　No, you can't.
8

しる vs. しっている: To find out vs. to know

The う-verb 知(し)る refers to a change from not knowing to knowing something. Depending on the context, it can mean “to find out,” “to learn about,” or “to come to know.”

  • New Kanji: 知 [Kun reading: し…; On reading: ち] The kanji 知 has the basic meaning “know; knowledge.” In this lesson, you will see it frequently in different forms of the verb 知(し)る (“to find out; to come to know”):

Because 知る refers to a change, the resultant-state form 知っている is normally used to describe someone's current state of knowledge:

  • 知る not know → find out / come to know
  • 知っている → be in the resulting state of knowing
For example:
  • 私はスミスさんを知っています。前に会ったことがありますから。 I know Mr. Smith. I have met him before.
Thus, English “I know ...” normally corresponds to Japanese 知っています, not 知ります.

The Negative Form: 知りません／知らない

The negative is exceptional. To say that someone does not know, Japanese normally uses 知りません (plain: 知らない), rather than 知っていません:
  • 私はスミスさんを知りません。会ったことがありませんから。 I don't know Mr. Smith. I have never met him.

Compare:

  • 知っています。　　 I know.
  • 知りません。　　 I don't know.
In casual conversation:
  • A: 「となりのトトロ」というアニメを知って(い)る？ 　　Do you know an anime called My Neighbor Totoro?
  • B: うん、知って(い)る。 　　Yeah, I do. or B: ううん、知らない。 　　No, I don't.

知った／知りました: found out; learned

The simple past form 知った／知りました refers to the event or point at which someone acquired new knowledge. It therefore often corresponds to English “found out,” “learned,” or “learned about.”
  • そのニュースはきのう知りました。 I found out about that news yesterday.
  • 日本に来て、はじめてこのアニメを知りました。 I first learned about this anime after coming to Japan.
Once that change has taken place, 知っている describes the resulting state:
  • きのう、そのニュースを知りました。 I found out about the news yesterday. → 今、そのニュースを知っています。 Now I know about the news.
Be careful not to translate 知る and 知っている in the same way:
  • スミスさんを知っています。 I know Mr. Smith. → current state
  • スミスさんのことを知りました。 I learned about Mr. Smith. → change/event
FYI: When talking about becoming personally acquainted with someone, however, Japanese often uses 知り合(あ)う rather than 知る:
  • アメリカに行った時(とき)、スミスさんと知り合(あ)いました。 I got to know / became acquainted with Mr. Smith when I went to America.
The important contrast is:
  • 知る／知った → acquiring knowledge (change)
  • 知っている → having that knowledge (resulting state)
  • 知らない／知りません → not knowing (negative state)
L14-Grammar