N5 · UNIT 10

Plain Form I いく・いかない

The plain forms, how Japanese actually sounds between friends, plus saying what you think.

About this unit

The biggest gear-shift in the course. Japanese has a polite register and a friend register, and this unit teaches the second: the plain forms 行く, 行かない, 行った, plus とおもいます for saying what you think. Maria makes her first real friend, and the textbook politeness drops away.

じしょけい（食べる・行く・する・くる）～ない（食べない・行かない）～た／～なかった～とおもいます

語彙 · Vocabulary 42 words · 10 kanji

Read the words 語彙

Read straight down the list once, out loud if you can. Don't grind them here, the Anki deck at the bottom does the memorizing. Right now you only want the shapes and sounds to feel familiar.

Word	Reading	Meaning
海	うみ	sea; beach
天気	てんき	weather
天気予報	てんきよほう	weather forecast
晴れ	はれ	sunny weather; clear skies
晴れます	はれます	to clear up (weather)
曇り	くもり	cloudy weather
雨	あめ	rain
降ります	ふります	to fall (rain, snow)
雪	ゆき	snow
風	かぜ	wind
空	そら	sky
星	ほし	star
東	ひがし	east
西	にし	west
南	みなみ	south
北	きた	north
春	はる	spring
夏	なつ	summer
秋	あき	autumn; fall
冬	ふゆ	winter
傘	かさ	umbrella
帽子	ぼうし	hat; cap
タオル	タオル	towel
水着	みずぎ	swimsuit
プール	プール	swimming pool
泳ぎます	およぎます	to swim
遊びます	あそびます	to play; to hang out
歌います	うたいます	to sing
歌	うた	song
思います	おもいます	to think
多分	たぶん	probably
うん	うん	yeah; uh-huh (casual はい)
ううん	ううん	nah; no (casual いいえ)
じゃあ	じゃあ	well then
本当	ほんとう	truth; really
うそ	うそ	lie; "no way!"
早い	はやい	early; fast
早く	はやく	early; quickly
遅い	おそい	late; slow
休み	やすみ	day off; vacation
辞書	じしょ	dictionary
言葉	ことば	word; language

Learn the kanji 漢字

The 10 kanji for this unit. Tap any card to flip between its meaning and its readings, and say the reading aloud as it flips.

天

heaven; sky

気

spirit; air

雨

rain

空

sky; empty

私

I; private

東

east

西

west

南

south

北

north

早

early

Read it in context 会話

Everything above, working together. Read the conversation top to bottom, out loud. Every line is built only from words and kanji you have already met, so resist the English, tap a word only if you are truly stuck.

Show English

After class, Maria overhears two classmates making beach plans, but their Japanese sounds nothing like the textbook. Yamada-sensei explains the second gear of Japanese, and Maria's new friend Yuki gives her the chance to use it.

マリア

せんせい、いま、クラスメートが「あした、うみへ行く？」「うん、行く！」と話していました。「行きます」ではありませんか。

Sensei, just now my classmates were saying, 'Going to the beach tomorrow?', 'Yeah, going!' Isn't it supposed to be 行きます?

やまだ

「行く」も「行きます」も、おなじですよ。「行きます」はていねいなことばです。「行く」は友だちのことばです。

行く and 行きます are the same word. 行きます is the polite one; 行く is the one for friends.

マリア

じゃ、「食べます」は？

Then what about 食べます?

やまだ

「食べる」です。「食べません」は「食べない」です。

It becomes 食べる. And 食べません becomes 食べない.

マリア

「します」と「来ます」は？

And します and 来ます?

やまだ

「する」と「くる」です。じしょには、この「行く」「食べる」が出ていますよ。だから、「じしょけい」です。

する and くる. Dictionaries list 行く and 食べる, not 行きます. That's why it's called the dictionary form.

ゆき

マリア、あした、いっしょにうみへ行かない？

Maria, wanna go to the beach with me tomorrow?

マリア

行く行く！でも、あしたの天気は？

Yes, absolutely! But what's tomorrow's weather?

ゆき

たぶん、はれるとおもうよ。あめはふらないとおもう。

It'll probably be sunny, I think. I don't think it'll rain.

マリア

よかった！じゃ、あした、早く行く？

Great! So, are we going early tomorrow?

ゆき

うん、あさ九時に駅で！じゃ、また、あした。

Yeah, 9 a.m. at the station! See you tomorrow.

マリア

うん！また、あした！

Yeah! See you tomorrow!

Notice: from Yuki's first line the dialogue shifts gears, no です, no ます anywhere. 行かない？ is a casual invitation (＝行きませんか), とおもう drops the います, and うん replaces はい. Maria even answers 行く行く！, doubling the verb for enthusiasm. Same Japanese, friend mode.

Stop, learn the vocabulary before the grammar

These units are short on purpose. The grammar only clicks when the words are already automatic, so front-load the deck here, and let spaced repetition do the memorizing while the lesson does the teaching.

Import this unit's deck. Generate it with npm run content:deck, then import n5-unit10-deck.apkg into Anki or Migaku. (SRS connection status lives on your dashboard.)
Learn all 42 words as new cards. Get through the whole deck in a sitting or two, you're aiming for recognition, not mastery yet.
Review daily until every card reaches a 3–5 day interval. When the whole deck has settled at that spacing, the words are holding on their own and won't fight you during the grammar.
Then come back. You'll read the patterns instead of decoding the words, and that's when a "small" unit actually soaks in.

Anki open with AnkiConnect? I can confirm the deck for you.

I've learned this unit's vocabulary deck to a 3 to 5 day review interval.

Tick the box above once the deck is soaking in, then the grammar unlocks.

文法 · Grammar 4 patterns

Take one pattern at a time. Read the rule, then read each example out loud until the shape feels obvious. The words should already be automatic from your deck, so all you are learning here is how they lock together.

Quick suggestion: write these patterns down by hand as you read them. It is the one habit that textbook learners and self-taught immersion learners both swear by, and a notebook is the cheapest memory upgrade there is. Not required, just recommended.

じしょけい（食べる・行く・する・くる）

The dictionary form (じしょけい), the plain non-past that dictionaries list. る-verbs: swap ます for る (たべます→たべる). う-verbs: the i-sound slides to the u-column (いきます→いく). Irregulars: します→する, きます→くる.

あした、としょかんへ行く。

I'm going to the library tomorrow. (casual)

毎日、コーヒーを飲む。

I drink coffee every day. (casual)

Note: Verbs ending in います slide to う: かいます→かう. And like ます, this one form covers both present habit and future, 行く is 'I go' and 'I will go.'

～ない（食べない・行かない）

The plain negative. る-verbs swap ます for ない (たべます→たべない). う-verbs slide the i-sound to the a-column and add ない (いきます→いかない, のみます→のまない).

きょうはテレビを見ない。

I'm not watching TV today. (casual)

あした、学校へ行かない。

I'm not going to school tomorrow. (casual)

Note: Two traps: かいます→かわない (the w-column, never かあない), and あります has no あら, its plain negative is simply ない.

～た／～なかった

The plain past and past negative. た borrows the て-form's sound changes exactly, swap て for た, で for だ. For the negative past, ない becomes なかった.

きのう、友だちとえいがを見た。

I watched a movie with a friend yesterday. (casual)

きょう、あさごはんを食べなかった。

I didn't eat breakfast today. (casual)

Note: If Unit 8's て-form changes are in your head, た is free: 行って→行った, 飲んで→飲んだ, 書いて→書いた. Past negative: 行かない→行かなかった.

～とおもいます

"I think that ~." Put the thought in plain form and add とおもいます, for opinions about the weather, plans, and people.

あした、あめがふるとおもいます。

I think it will rain tomorrow.

たなかさんは、きょうは来ないとおもいます。

I don't think Mr. Tanaka is coming today.

Note: The thought stays plain even when the sentence is polite, ふるとおもいます, never ふりますとおもいます. と works like quotation marks around the thought. To ask an opinion: どうおもいますか。

文化 · Culture note

A short read on the world these words live in. Nothing to drill here, just the context that makes the grammar feel like something people actually say.

The Two Gears of Japanese です・ますとタメぐち

Japanese runs on two gears. です・ます, the polite gear you've driven for nine units, is for teachers, bosses, shop staff, strangers, and anyone older than you. The plain form, casually called タメぐち, is for family, close friends, and children. The words and the grammar are identical; only the endings shift. 行きます and 行く mean exactly the same thing, to two different listeners.

Textbooks teach the polite gear first for a simple reason: です・ます is never wrong. Sound a little stiff with a friend and you get a smile; use casual with your boss and you've called a stranger 'buddy', people will forgive a learner, but it lands like a small slap. The plain form also turns out to be the engine room of the language: it's what goes before とおもいます this unit, and before dozens of structures later. Even the most formal speech has plain forms humming inside it.

The switch itself is a social event. Japanese friends will often invite you down a gear, タメぐちでいいよ, 'casual is fine', and the moment a classmate drops ます with you, the friendship has officially upgraded. Until then, keep polite as your default; after it, staying stiffly polite can read as keeping your distance.

Try it: Don't downshift first. Let the other person drop です・ます, then match them, the gear change is theirs to offer.

練習 · Worksheet 8 exercises

Type each answer in hiragana, then check. Most items convert polite forms to plain, the switch you'll make every day with friends.

（1）「食べます」のじしょけいは？（ひらがなで）

（2）あした、うみへ（　　）？, casual: “Going to the beach tomorrow?”

（3）きょうはテレビを（　　　）。, casual: “I'm not watching TV today.”

（4）「飲みます」→（　　　　）, plain negative: “don't drink.”

（5）きのう、パンを（　　　）。, casual past: “I ate bread yesterday.”

（6）「のみました」→（　　　）, casual past: “drank.”

（7）「あります」→（　　）, plain negative: “there isn't.”

（8）あした、あめがふる（　　　　　　）。, “I think it will rain tomorrow.”

Check your answers to continue, it doesn't matter how many you miss.

Unit Quiz JLPT FORMAT

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