When you learned how to build ます, you produced a short stem — 書き, 食べ, 飲み — and then bolted ます onto it. It is tempting to think of that stem as nothing more than "the thing before ます." That would be a mistake. The stem, whose grammatical name is the 連用形（れんようけい）, is one of the busiest forms in the entire language. It becomes a noun, it fuses verbs into compounds, and it heads the "go and do" construction. One form, three jobs — and once you see it, a whole layer of Japanese vocabulary becomes transparent.
The same stem, four hats
The 連用形 is the い-row stem you already know: godan verbs shift to the い-row (休む → 休み, 帰る → 帰り), ichidan verbs drop る (食べる → 食べ). Here is the map of what it does:
| Job | Example | Result |
|---|---|---|
| Polite base | 飲み + ます | 飲みます (drinks) |
| Noun | 休む → 休み | a rest, a holiday |
| Compound verb | 読み + 終わる | 読み終わる (finish reading) |
| Purpose (〜に行く) | 食べ + に行く | 食べに行く (go to eat) |
We covered the first job in the ます pages. The other three are what this page is about.
Job 1: the stem as a noun
Take a verb, strip it to its 連用形, and very often you are left with a real, dictionary-listed noun — one that means "the act/result of doing the verb."
| Verb | 連用形 noun | Meaning of the noun |
|---|---|---|
| 休む（やすむ, to rest） | 休み | a rest, a break, a holiday |
| 帰る（かえる, to go home） | 帰り | the way home, the return |
| 始める（はじめる, to begin） | 始め | the beginning, the start |
| 楽しむ（たのしむ, to enjoy） | 楽しみ | a pleasure, something looked forward to |
| 考える（かんがえる, to think） | 考え | a thought, an idea, an opinion |
昼休みは一時からです。
hiruyasumi wa ichiji kara desu
The lunch break is from one o'clock.
帰りにスーパーに寄ります。
kaeri ni sūpā ni yorimasu
I'll stop by the supermarket on the way home.
楽しみにしています。
tanoshimi ni shite imasu
I'm looking forward to it.
That third sentence is a fixed phrase every learner uses, and now you can see it is built from 楽しむ. This is the payoff: because so many everyday nouns are frozen 連用形 forms — 始め (beginning), 疲れ（つかれ, fatigue, from 疲れる）, 遊び (play, from 遊ぶ), 動き（うごき, movement, from 動く）, 願い（ねがい, a wish, from 願う）— recognizing the stem turns opaque vocabulary into transparent verb derivatives. You stop memorizing 話（はなし, a story/talk）as an unrelated word and see it as 話す's stem.
Job 2: compound verbs
Glue the 連用形 of one verb to the front of a second verb and you get a compound verb whose meaning combines the two. The first verb keeps its 連用形; the second verb carries all the conjugation. This is how Japanese builds much of its everyday nuance.
| Stem + verb | Compound | Meaning |
|---|---|---|
| 読み + 終わる | 読み終わる | to finish reading |
| 食べ + すぎる | 食べすぎる | to overeat |
| 食べ + 始める | 食べ始める | to start eating |
| 降り + 続ける | 降り続ける | to keep falling (rain, snow) |
| 言い + 忘れる | 言い忘れる | to forget to say |
本をもう読み終わった。
hon o mō yomiowatta
I've already finished reading the book.
ちょっと食べすぎたかな。
chotto tabesugita ka na
Hmm, I think I ate a bit too much.
雨が朝から降り続けている。
ame ga asa kara furitsuzukete iru
It's been raining nonstop since this morning.
The pattern scales enormously: 〜始める (start doing), 〜終わる (finish doing), 〜続ける (keep doing), 〜すぎる (do too much), 〜忘れる (forget to do), 〜直す（なおす, redo）, 〜合う（あう, do to each other）. All of them attach to the 連用形. Learn the joint and you unlock hundreds of verbs. The closely related する-compounds (勉強する, 電話する) work on the same logic and are covered in する compound verbs.
Job 3: 〜に行く — going somewhere to do something
To say you go/come somewhere in order to do something, put the verb's 連用形 before に行く（いく） or に来る（くる）. The stem names the purpose; 行く or 来る carries the motion and the tense.
映画を見に行きます。
eiga o mi ni ikimasu
I'm going to see a movie.
週末は友達が遊びに来ます。
shūmatsu wa tomodachi ga asobi ni kimasu
A friend is coming over to hang out this weekend.
お昼、一緒に食べに行きませんか。
ohiru, issho ni tabe ni ikimasen ka
Want to go grab lunch together?
You will also meet the noun version: 買い物に行く（かいものにいく, to go shopping）is literally 買い (the stem of 買う) + 物 (thing) + に行く — "go for the buying-of-things." Once you can spot the 連用形 inside 買い物, the phrase stops being a memorized lump and becomes a small piece of grammar you can take apart.
午後、買い物に行きます。
gogo, kaimono ni ikimasu
I'm going shopping this afternoon.
Common mistakes
❌ 本を読む終わった。
Wrong — the dictionary form was used before 終わる.
✅ 本を読み終わった。
hon o yomiowatta
Correct — compounds attach to the 連用形 stem 読み.
❌ 食べる始めた。
Wrong — kept る instead of using the stem.
✅ 食べ始めた。
tabehajimeta
Correct — 食べ + 始める.
❌ 買うに行きます。
Wrong — the dictionary form was used before に行く.
✅ 買いに行きます。
kai ni ikimasu
Correct — the 連用形 買い names the purpose.
❌ 見ますに行きます。
Wrong — the polite ます form was stacked before に行く.
✅ 見に行きます。
mi ni ikimasu
Correct — only the final verb 行く is polite; the purpose verb stays a bare stem.
Key takeaways
- The 連用形 is the い-row stem — the same one します rides on — but it lives a rich independent life.
- As a noun it names the act (休み a break, 帰り the way home, 楽しみ a pleasure), which makes much everyday vocabulary transparent.
- As a compound base it fuses with 終わる, 始める, すぎる, 続ける, and dozens more.
- With 〜に行く / 〜に来る it expresses purpose (食べに行く go to eat), always as a bare stem — never ますに行く.
Now practice Japanese
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Start learning Japanese→Related Topics
- The ます Polite FormN5 — How 〜ます turns a verb into its polite non-past form — the register-neutral default you use with strangers — without changing the verb's meaning at all.
- Forming ます Across the ClassesN4 — The mechanical rule for building the ます-stem in every verb class — the godan い-row kana shift, the ichidan る-drop, and the two irregulars — so ます becomes automatic.
- する-Compound Verbs (勉強する・電話する)N4 — Noun + する verbs a noun (勉強する, 電話する, 予約する) — an enormously productive pattern where only する ever conjugates and the noun sometimes detaches with を, word by word.