The short version: delete ます from a polite verb and what is left is the ます-stem: 食べます → 食べ, 読みます → 読み. At least fifteen N5–N4 grammar points plug straight into it — たい, に行く, ながら, 方, やすい, にくい, すぎる, 始める, 終わる, 続ける, そう, なさい and more. The one rule to remember: after you plug something in, the new word conjugates like the thing you plugged in.
Grammar lists make N4 look like a wall: forty, fifty, sixty separate patterns, each with its own page in the textbook. Learners memorise them one at a time and forget them one at a time. What the lists do not show is that a large share of those patterns are the same move repeated — take one verb form, add one ending. Once you see the form, a new pattern is not a new structure to learn; it is one new ending on something you already produce every day.
That form is the ます-stem. Japanese grammarians call it 連用形, the continuative form, because its job is to connect a verb to whatever comes next.
Step 1: build the stem (you already know how)
The easy way: say the ます form and stop before ます. If you want to go from the dictionary form, there are only four cases:
書く→書き
飲む→飲み
買う→買い
食べる→食べ
見る→見
起きる→起き
する→し
勉強する→勉強し
来る→来
Written 来, read き.
Watch out for the fake ichidan verbs — godan verbs that end in いる/える, such as 帰る and 入る. Their stems are 帰り and 入り, not 帰 and 入. If you are ever unsure, the ます form settles it (帰ります). The free Kanjijo verb conjugator shows the class of every N5–N4 verb and the exact rule applied.
Step 2: see the socket
The colours are the important part. They tell you what the verb turns into once the ending is plugged in — and therefore how it conjugates afterwards. That single idea removes most of the conjugation confusion around these patterns, so it gets its own section after the tour.
Step 3: the fifteen plugs
Group A — the everyday four (N5)
一緒に食べましょう。いっしょにたべましょう。Let's eat together.
You have been using the stem since day one without noticing. Every polite form is stem + an ending. The invitation forms ましょう / ませんか are compared in ましょう vs ませんか vs ましょうか.
日本へ行きたいです。にほんへいきたいです。I want to go to Japan.
今日は何も食べたくないです。きょうはなにもたべたくないです。I don't want to eat anything today.
たい turns the verb into an い-adjective, so it conjugates like one: たくない, たかった. With a direct object you can keep を or switch to が: 水が飲みたい. Use it for yourself; for other people, Japanese prefers 〜たがっています (see how to say what you want).
友だちと映画を見に行きます。ともだちとえいがをみにいきます。I'm going to see a film with a friend.
に marks the purpose of the movement. It only works with verbs of motion — 行く, 来る, 帰る. With a する-noun you can drop する: 買い物に行きます.
This is the plug you already know without knowing it. Many beginner nouns are simply stems, or a stem plus 物 (thing) or 場 (place):
| Noun | Built from | Meaning |
|---|---|---|
| 飲み物 | 飲み + 物 | a drink (“drink-thing”) |
| 食べ物 | 食べ + 物 | food |
| 買い物 | 買い + 物 | shopping |
| 乗り場 | 乗り + 場 | boarding place, platform (every taxi and bus sign) |
| 休み | 休む | a holiday, a break |
| 帰り | 帰る | the way home |
Now you can decode new words on sight: 忘れ物 = forget-thing = something left behind, which is exactly what the lost-property sign at a station says.
Group B — how, while, and how easily (N4)
音楽を聞きながら勉強します。おんがくをききながらべんきょうします。I study while listening to music.
The main action goes last. The ながら verb is the background; the final verb is what you are really doing. Both actions must belong to the same person — for two different people, use 〜間に.
この漢字の読み方を教えてください。このかんじのよみかたをおしえてください。Please tell me how to read this kanji.
方 turns the verb into a noun, so を becomes の. 漢字を読む → 漢字の読み方. Forgetting this particle change is the most common error with this pattern. Useful set: 使い方 (how to use), 作り方 (recipe), 行き方 (how to get there).
この本は字が大きくて、読みやすいです。このほんはじがおおきくて、よみやすいです。This book has big print, so it's easy to read.
この靴は歩きにくいです。このくつはあるきにくいです。These shoes are hard to walk in.
Both are い-adjective endings: 分かりやすくない, 読みにくかった. The subject is the thing (the book, the shoes), not the person. At N3 you will meet 〜づらい, which is closer to hard for me, uncomfortable to — a personal difficulty rather than a property of the object.
Group C — start, finish, keep going, too much (N4)
先月から日本語を習い始めました。せんげつからにほんごをならいはじめました。I started learning Japanese last month.
急に雨が降り出しました。きゅうにあめがふりだしました。It suddenly started to rain.
始める is a neutral start; 出す is a sudden, unplanned one — rain, crying, laughing, running. Note that 始める is ichidan (始めます) while 出す is godan (出します). The compound keeps the class of its second half.
この本はもう読み終わりました。このほんはもうよみおわりました。I've already finished reading this book.
三時間歩き続けました。さんじかんあるきつづけました。I kept walking for three hours.
Compare with the もう in the first example — もう vs まだ explains why it means already here. 終わる is godan; 続ける is ichidan.
ゆうべ飲みすぎて、頭が痛いです。ゆうべのみすぎて、あたまがいたいです。I drank too much last night and my head hurts.
すぎる is an ichidan verb: すぎます, すぎた, すぎて. It also attaches to adjectives with the い or な removed — 高すぎる (too expensive), 静かすぎる (too quiet) — with one irregular: いい → よすぎる. The noun form すぎ is everyday speech: 食べすぎ (overeating).
Group D — looks like, command, honorific (N4)
空が暗いですね。雨が降りそうです。そらがくらいですね。あめがふりそうです。The sky is dark. It looks like it's going to rain.
Stem + そう → I can see it
降りそうです。
ふりそうですIt looks like it will rain.
Plain + そう → I heard it
降るそうです。
ふるそうですI hear it's going to rain.
The verb form in front of そう changes the meaning completely. Stem = your own judgement from what you see. Plain form = hearsay. Stem + そう behaves as a な-adjective: 落ちそうな荷物 (luggage that looks about to fall). The full comparison is in そうだ・らしい・ようだ.
早く寝なさい。はやくねなさい。Go to bed now.
This is what parents say to children and what test instructions say to candidates (正しいものを選びなさい, choose the correct one). You will read it far more often than you say it — using it to an adult sounds like scolding.
少々お待ちください。しょうしょうおまちください。Please wait a moment.
The sentence you hear in every shop, hotel and station. お待ちください is the stem of 待つ wrapped in お〜ください — more respectful than 待ってください. Others you will hear daily: お入りください, お座りください, お気をつけください (mind your step). More in the keigo guide.
The rule that removes half the confusion: the plug decides the conjugation
Learners often ask how to make 食べたい negative, or 読み始める past. The answer is always the same: stop thinking about the original verb. Once the ending is plugged in, you have a new word, and it conjugates according to the ending.
| Ending | The new word is… | Negative | Past |
|---|---|---|---|
| たい / やすい / にくい | い-adjective | 食べたくない | 読みやすかった |
| すぎる / 始める / 続ける | ichidan verb | 食べすぎない | 読み始めた |
| 終わる / 出す | godan verb | 読み終わらない | 降り出した |
| そう | な-adjective | 降りそうもない | 降りそうだった |
| 方 / 物 | noun | Does not conjugate; takes の before it: 漢字の読み方 | |
The four mistakes this pattern prevents
聞くながら
聞きながらききながらwhile listening
行くたい
行きたいいきたいwant to go
漢字を読み方
漢字の読み方かんじのよみかたhow to read kanji
食べたいません
食べたくないですたべたくないですI don't want to eat
Check yourself — plug it in
Choose the correct form. Each answer names the rule.
テレビを ＿＿ ごはんを食べます。
ながら takes the stem: 見る → 見 → 見ながら.
行き ＿＿。
行きたい is an い-adjective: past negative = たくなかった(です).
この機械 ＿＿ 使い方が分かりません。
方 makes a noun, so を becomes の.
雨が ＿＿ そうです。 (you can see it coming)
Stem + そう = it looks like. 降るそう would mean I hear it will rain.
ケーキを ＿＿。
Stem + すぎる, and すぎる is ichidan: すぎます → すぎました.
帰る → ＿＿ たい
帰る is a fake ichidan — it is godan (帰ります), so the stem is 帰り.
Reference summary
- What it is
- The ます-stem (連用形) = polite form minus ます. 食べます → 食べ; 書きます → 書き; します → し; 来ます → 来 (き).
- Building it
- Godan: last syllable to the い-row (書く→書き). Ichidan: drop る (食べる→食べ). Watch fake ichidan: 帰る→帰り, 入る→入り.
- N5 plugs
- ます family · たい (want) · に行く/来る (go to do) · 物/場 and stems as nouns (飲み物, 乗り場, 休み).
- N4 plugs
- ながら (while) · 方 (how to) · やすい / にくい (easy / hard to) · 始める / 出す (start / burst into) · 終わる (finish) · 続ける (keep) · すぎる (too much) · そう (looks like) · なさい (command) · お〜ください (honorific please).
- Conjugation rule
- The ending decides: たい/やすい/にくい = い-adjective; すぎる/始める/続ける = ichidan; 終わる/出す = godan; そう = な-adjective; 方/物 = noun.
- Top traps
- 読むながら ✗ → 読みながら. 漢字を読み方 ✗ → 漢字の読み方. 降りそう (looks like) ≠ 降るそう (I hear).
Related Reading on Kanjijo
Frequently Asked Questions
The part of a polite verb left when ます is removed: 食べます → 食べ, 飲みます → 飲み, します → し, 来ます → 来 (き). Japanese grammar calls it 連用形, the continuative form.
Delete ます from the polite form. From the dictionary form: godan verbs move the last syllable to the い-row (書く→書き), ichidan verbs drop る (食べる→食べ), する→し, 来る→き.
At N5–N4: ます forms, たい, に行く, ながら, 方, やすい, にくい, すぎる, 始める, 出す, 終わる, 続ける, そう, なさい and お〜ください — plus nouns like 飲み物, 乗り場 and 休み.
Like the ending. たい, やすい and にくい are い-adjectives: 食べたくない, 分かりやすかった. すぎる is ichidan (食べすぎた); 終わる is godan (読み終わった); そう is a な-adjective (降りそうな空).
降りそうです (stem) = it looks like it will rain, from what you can see. 降るそうです (plain form) = I hear it will rain. The verb form before そう changes the meaning.
- The Japan Foundation & JEES, JLPT Level Summary — the official can-do description of N5 and N4, the levels where these patterns are tested.
- The Japan Foundation & JEES, JLPT sample questions — official grammar (文法) items showing the formats used for these patterns.
Stop collecting patterns. Start plugging them in.
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