Lesson 20 of 50 · 行く・忙しい・スパイだ · みんなの日本語 第20課 · N5

Story voice: 〜 N3–N2 Japanese — above this lesson’s level, on purpose. Your target is the Key Sentences.

Episode 20: The Inner Voice

Mini Story

A spy has two voices. The outer voice is polite — measured, careful, formal. The inner voice is plain — direct, urgent, true. In the gap between the two, Mike lives.间谍有两个声音。外面的声音是礼貌的——克制、谨慎、正式。里面的声音是素的——直接、急迫、真实。麦克就活在这两个声音的缝隙里。間諜有兩個聲音。外面的聲音是禮貌的——克制、謹慎、正式。裡面的聲音是素的——直接、急迫、真實。麥克就活在這兩個聲音的縫隙裡。Điệp viên có hai giọng nói. Giọng bên ngoài thì lễ độ — chừng mực, thận trọng, trang trọng. Giọng bên trong thì trần trụi — thẳng, gấp, thật. Mike sống trong khe hở giữa hai giọng nói ấy.
スパイ は 二ふたfutaつの声こえkoeを持もmoつ。 外そとsotoの声こえkoeは丁寧ていねいteinei ── 抑制よくせいyokuseiされた、 慎重しんちょうshinchouな、 formal な。 内ないnaiの声こえkoeは plain ── 直接的ちょくせつてきchokusetsutekiで、 切迫せっぱくseppakuした、 真実しんじつshinjitsuの。 二ふたfutaつの間あいだaidaの隔へだhedaたりに、 マイクは生いiきている。

The outer voice tells the office: a trip, for personal reasons. The inner voice tells the truth.外面的声音对办公室说：因私出差。里面的声音，说的是真话。外面的聲音對辦公室說：因私出差。裡面的聲音，說的是真話。Giọng bên ngoài nói với văn phòng: một chuyến đi, vì việc riêng. Giọng bên trong nói sự thật.
外そとsotoの声こえkoeは オフィス に告つtsuげる。 個人的こじんてきkojintekiな事情じじょうjijouの出張しゅっちょうshutchou、 と。 内ないnaiの声こえkoeは、 真実しんじつshinjitsuを告つtsuげる。

The polite mask: 「仕事しごとshigotoは 大変たいへんtaihenですね」 (work is hard). The plain truth — same words, no mask:
丁寧ていねいteineiな仮面かめんkamen ──「仕事しごとshigotoは 大変たいへんtaihenですね」。 plain な真実しんじつshinjitsu ── 同おなonaじ言葉ことばkotoba、 仮面かめんkamenなし。

To others, he is an analyst. A middle-aged man with no spouse. A coffee drinker. To himself —在别人眼里，他是分析员。没有配偶的中年男人。爱喝咖啡的人。而在自己眼里——在別人眼裡，他是分析員。沒有配偶的中年男人。愛喝咖啡的人。而在自己眼裡——Với người khác, anh là một nhà phân tích. Một người đàn ông trung niên không vợ. Một kẻ nghiện cà phê. Còn với chính mình —
他ほかhokaの人にんninにとって、 彼かれkareは分析ぶんせきbunseki家いえie。 配偶者はいぐうしゃhaiguushaのいない中年男性ちゅうねんだんせいchuunendansei。 コーヒー 飲のnoみ。 自分じぶんjibunにとっては ──

And the one rule — spoken inside, without the polish of です・ます, sharper for it:还有一条规则。在心里说，不加です・ます的打磨，更锋利——還有一條規則。在心裡說，不加です・ます的打磨，更鋒利——Và một luật duy nhất. Được nói ở bên trong, không có lớp bóng của です・ます, sắc hơn —
そして、 ひとつの規則きそくkisoku。 内側うちがわuchigawaで語かたkataられる、 です・ますの磨みがmigaきなしで、 鋭するどsurudoく ──

Chapter 2: Schedules and Hidden Truths →

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Key Sentences

convert each from polite to plain.

1. Verb plain present (行いiく)

2. な-adj plain (大変たいへんtaihenだ)

3. Noun plain (スパイだ)

4. V-なければ いけない (plain must)

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Practice out loud

Say the answer before you look. The same sentences you just read — now from your own mouth.

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Vocabulary

note the polite vs plain pairs.

日本語 (plain)	です・ます form	English	简体	繁體	Tiếng Việt
行いiく マイクは 今日きょうkyou 京都きょうとkyoutoに 行いiく。	行いiきます	go Mike is going to Kyoto today.	去 麦克今天去京都。	去 麥克今天去京都。	đi Hôm nay Mike đi Kyoto.
来くkuる あした 友達ともだちtomodachiが 来くkuる。	来きkiます	come My friend is coming tomorrow.	来 明天朋友来。	來 明天朋友來。	đến Ngày mai bạn tôi đến.
する 今いまimaから 仕事しごとshigotoを する。	します	do I'm going to work now.	做 我现在开始工作。	做 我現在開始工作。	làm Bây giờ tôi bắt đầu làm việc.
食たtaべる 朝あさasaごはんを 食たtaべる。	食たtaべます	eat I eat breakfast.	吃 我吃早饭。	吃 我吃早餐。	ăn Tôi ăn sáng.
飲のnoむ コーヒーを 飲のnoむ。	飲のnoみます	drink I drink coffee.	喝 我喝咖啡。	喝 我喝咖啡。	uống Tôi uống cà phê.
だ マイクは スパイだ。	です	copula (is) Mike is a spy.	是 麦克是间谍。	是 麥克是間諜。	là Mike là điệp viên.
ない 時間じかんjikanが ない。	ありません	not exist / negative There is no time.	没有 没有时间。	沒有 沒有時間。	không có Không có thời gian.
大変たいへんtaihen 仕事しごとshigotoは 大変たいへんtaihenだ。	大変たいへんtaihenです	hard, tough The work is tough.	辛苦 工作很辛苦。	辛苦 工作很辛苦。	vất vả Công việc vất vả.
簡単かんたんkantan この 問題もんだいmondaiは 簡単かんたんkantanだ。	簡単かんたんkantanです	simple, easy This question is simple.	简单 这个问题很简单。	簡單 這個問題很簡單。	đơn giản Câu hỏi này đơn giản.
忙いそがisogaしい 今日きょうkyouは 忙いそがisogaしい。	忙いそがisogaしいです	busy Today is busy.	忙 今天很忙。	忙 今天很忙。	bận rộn Hôm nay bận.
面白おもしろomoshiroい この 本ほんhonは 面白おもしろomoshiroい。	面白おもしろomoshiroいです	interesting This book is interesting.	有意思 这本书很有意思。	有意思 這本書很有意思。	thú vị Quyển sách này thú vị.

Practice these words →

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Grammar Patterns

focus on the present/past, positive/negative grid.

Grammar Picture

• 名詞noun名词danh từ
• 述語sentence ending句尾句尾phần cuối câu

普通形ふつうけいfutsuukei: plain form — how Japanese is written, and how friends speak to each other.

When to use plain form

Plain form (普通形ふつうけいfutsuukei) is used in:

• Writing: novels, news articles, journal entries
• Casual conversation: with close friends, family, children
• Inner thought: when describing what someone thinks/feels
• Subordinate clauses: before と思おもomoう, と言いiう, から, など — required regardless of formality

Polite form (です・ます) is used when meeting someone, talking to superiors, in business / customer service.

Plain form conjugation summary

Verb (G1):

• Present: 行いiく / 行いiかない
• Past: 行いiった / 行いiかなかった

Verb (G2):

• Present: 食たtaべる / 食たtaべない
• Past: 食たtaべた / 食たtaべなかった

Noun:

• Present: 学生がくせいgakuseiだ / 学生がくせいgakuseiじゃない
• Past: 学生がくせいgakuseiだった / 学生がくせいgakuseiじゃなかった

い-adj:

• Present: 忙いそがisogaしい / 忙いそがisogaしくない
• Past: 忙いそがisogaしかった / 忙いそがisogaしくなかった

な-adj:

• Present: 静しずshizuかだ / 静しずshizuかじゃない
• Past: 静しずshizuかだった / 静しずshizuかじゃなかった

Reading practice — plain form in stories

Most Japanese books, manga, news, and song lyrics are in plain form. Once you learn plain form, you unlock a vast reading world.

Try reading easy news: NHK NEWS WEB EASY (https://www3.nhk.or.jp/news/easy/) — plain-form simplifications of real news.

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Roleplay Practice

practice casual conversation in plain form.

Scene: Two close friends talking — casual register, all plain form.

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How do you say this in Japanese?

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How to Use This Lesson

Read the sections in the order they appear. About 40 minutes.
Tomorrow, come back — convert 5 polite sentences from your notes into plain.

For Teachers

For Teachers (45-60 minutes in class)

• Warm-up (5 min): Convert 10 polite sentences to plain on the board.
• Grid drill (15 min): Fill in the present/past × positive/negative grid for verb, noun, adj.
• Reading practice (10 min): Read a short manga page in plain form. Identify the plain forms.
• Plain conversation (15 min): Pairs practice in plain form. Notice the relational vibe shifts.
• Check Yourself (5-10 min).

Cultural note: Plain form is required in some grammatical structures (before と思おもomoう, と言いiう, から in casual) but only as a casual register otherwise. Code-switching between plain and polite is a skill — knowing when to drop です is part of native-like Japanese.

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← Lesson 19 | Midnight Encounter | Lesson 21 →

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