Compound Verbs in Japanese (複合動詞): The V1-Stem + V2 Pattern

Compound verbs in Japanese (複合動詞 fukugō dōshi) are single verb words built by attaching one verb to another in the shape V1-stem + V2.¹ This pattern is one of the most productive parts of Japanese verb morphology. Kageyama estimates that the language has compound verbs "probably on the order of several thousands."¹

Overview

What counts as a compound verb

A compound verb is one verb word made of two verbs joined as V1-stem + V2. The combined sequence behaves as a single phonological and morphological word.¹ Focus particles like さえ, も, and だけ cannot slip between V1 and V2. Gapping also cannot delete only the first verb out of a compound.¹

The abstract shape is "infinitive (V1) + infinitive (V2)." Here, "infinitive" means the form usually called the 連用形 (ren'yōkei) or masu-stem.¹ The masu-stem is the same form learners already meet in polite ます endings and in deverbal nouns (nouns made from verbs) like 読み or 始め.²

Two nearby constructions look similar but work differently. て-form chaining links two predicates with て (食べて始める is "eat and then start," two verbs). Noun + する (勉強する) is a noun verbalised by する, not a V-V compound.¹

The single-word test

A true compound verb resists focus-particle intrusion. *食べさえ始める is ungrammatical on a compound-verb reading, which shows that 食べ始める is one word, not two stacked predicates.¹

Why this matters at N3

The NINJAL Compound Verb Lexicon (複合動詞レキシコン) contains over 2,700 entries of common contemporary V-V compounds. Roughly 2,000 entries were compiled by Taro Kageyama from dictionary and corpus sources, with the remainder added by Kyoko Kanzaki from major works on the topic.³⁴ The lexicon catalogues only lexical compound verbs. Its rationale is that "syntactic compound verbs, which are excluded from the database, are easily recognizable and interpretable, and unlike lexical compound verbs, which are severely restricted in the combinations of the first and second verbs, syntactic compound verbs may accommodate any verb in the position indicated."³

The lexicon's stated audience is both linguistic researchers and foreign learners.³ Once you control the masu-stem, the V-V pattern unlocks a large slice of intermediate vocabulary. It also gives you a productive way to coin new verbs on the fly.¹³

Scope of this article

This article fixes the general V1-stem + V2 rule and names the lexical-vs-syntactic split. It introduces specific V2 families at a concept level here. These include the aspectual ～始める / ～終わる / ～続ける, plus directional, completive, or manner V2 like ～出す, ～切る, ～込む, ～直す. Each family is covered in full in its own dedicated article.

Form: the V1-stem + V2 rule

Step 1, take V1 to its masu-stem (連用形)

The masu-stem, also called the 連用形 (ren'yōkei) or "infinitive," is formed by removing ます from the polite present.²⁵ This is the same stem used before the ます ending, in the chūshi clause linker, and in many deverbal nouns.²

Standard godan and ichidan reductions apply: 読む becomes 読み, 書く becomes 書き, 取る becomes 取り, 食べる becomes 食べ, and 始める becomes 始め.²⁵ The two irregular verbs become 来る → 来 (き) and する → し.²

The diagram below shows how the same masu-stem feeds compound formation and other shapes:

飛とぶ → 飛とび²
"to fly / to jump → flight-stem"

食たべる → 食たべ²
"to eat → eat-stem"

Step 2, attach V2 in its dictionary form

V2 enters in its plain (dictionary) form and provides the inflectional handle for the whole word.¹⁵ Kageyama's exhibit list includes lexical pairings such as 取り組む (tori-kumu, "tackle"), 飛び出す (tobi-dasu, "jump out"), and 引き受ける (hiki-ukeru, "take on"). From the syntactic family, it includes 書き始める (kaki-hajimeru, "begin to write"), 食べ終える (tabe-oeru, "finish eating"), and 話し続ける (hanashi-tsuzukeru, "continue speaking").¹

仕事しごとに取とり組くむ。¹
"I tackle the work."

手紙てがみを書かき終おえた。¹
"I finished writing the letter."

Step 3, conjugate V2 only

V1 is frozen in its stem. Tense, polarity, politeness, te-form, ta-form, and potential all attach to V2.¹⁵ You conjugate the compound exactly as if V2 were the only verb in the word.

Form	Compound (飛び込む)	Where the marker sits
Plain nonpast	飛び込む	V2
Polite nonpast	飛び込みます	V2
Plain past	飛び込んだ	V2
Plain negative	飛び込まない	V2
te-form	飛び込んで	V2
Potential	飛び込める	V2

飛とび込こまない。⁶
"I don't jump in."

飛とび込こみます。⁶
"I jump in."

飛とび込こんだ。⁶
"I jumped in."

Conjugating V1 is the classic error

A learner who treats V1 as the inflecting verb produces *飛んだ込む for "jumped in." The correct form is 飛び込んだ: V1 stays in its ren'yōkei and only V2 carries tense.¹

Voicing and reading shifts

Rendaku (sequential voicing) is "rare in compounds of the form Verb + Verb" compared with Noun+Verb or Adjective+Noun compounds.⁷ One attested V-V case is 立ち止まる (tachi-domaru, from 止まる tomaru, "stop").⁷

For the common V2 set, the surface form usually keeps the V2 onset unchanged: 取り出す is toridasu (no rendaku on /d/), 飛び込む is tobikomu (no rendaku on /k/), and 読み始める is yomihajimeru (no rendaku on /h/).⁷ Voicing in compound verbs is therefore lexicalised compound by compound, rather than predictable from the V2 onset alone.⁷

Two kinds of compound verbs: lexical vs syntactic

Kageyama splits compound verbs into two families. The split is based on how the whole meaning relates to the meanings of the parts, and on a set of syntactic tests.¹ It predicts which compounds you can freely coin and which you must look up in a dictionary.

Lexical compounds (語彙的複合動詞)

Kageyama labels these "Type A." His list includes "uti-korosu 'shoot-kill = shoot to death,' nomi-aruku 'drink-walk = tour bars,' si-nokosu 'do-leave = leave undone,' kiki-kaesu 'ask-return = ask back,' oi-dasu 'chase-take-out = send out,' nage-suteru 'throw-abandon = throw away,' tobi-agaru 'throw-rise = jump up,' naki-yamu 'cry-stop = stop crying,' naki-sakebu 'cry-shout = cry and scream.'"¹

The two key properties are that "Type A compounds tend to have lexicalized or conventionalized meanings while type B compounds are semantically transparent," and that "Type A compounds are by and large limited to lexically specified combinations of V1 and V2."¹ In practice, treat each lexical compound as a vocabulary item, not as a phrase you build on the fly. The NINJAL Compound Verb Lexicon catalogues exactly this type.³

Argument structure for lexical compounds is constrained by Kageyama's Transitivity Harmony Principle. In his words: "Given the three argument structures below, lexical compound verbs are built by combining two verbs of the same type of argument structure. (a) transitive verbs (b) unergative intransitive verbs (c) unaccusative intransitive verbs."¹ Mixed combinations of transitive with unaccusative are ungrammatical (*tuki-otiru "push-fall," *osi-aku "push-open"), while transitive+unergative and unergative+transitive are attested.¹

取とり組くむ¹
"to tackle, to engage with"

飛とび出だす¹
"to jump out, to rush out"

引ひき受うける¹
"to take on, to accept"

Syntactic compounds (統語的複合動詞)

Kageyama labels these "Type B." His list includes "kaki-hazimeru 'write-begin = begin to write,' tabe-oeru 'eat-finish = finish eating,' hanasi-tuzukeru 'speak-continue = continue speaking,' ugoki-dasu 'move-begin = begin to move,' tabe-kakeru 'eat-set = be about to eat,' tasuke-au 'help-join = help each other,' tabe-sokoneru 'eat-miss = miss eating,' tabe-sugiru 'eat-pass = overeat,' ii-wasureru 'say-forget = forget to say,' tabe-tukusu 'eat-exhaust = eat up.'"¹

The key property is that "type B compounds basically have no lexical idiosyncrasies on the combinations of two components."¹ In practice, a syntactic V2 acts like a productive aspectual or modal suffix. You can build new compounds productively from any compatible V1.

Four diagnostics distinguish type B from type A: passivization in V1, honorification on V1, replacement of V1 by the proform そうする (sō suru "do so"), and admitting a verbal-noun (VN, a noun that can form a する verb) + する as V1.¹ All four are blocked for lexical (type A) compounds but allowed for syntactic (type B). For example, kaki-komu ("write into") rejects passivization in V1 (*kak-are-komu), whereas ais-are-tuzukeru ("continue to be loved") is grammatical.¹ On the proform test, *soo si-sakebu ("so do-shout") is bad, but soo si-tuzukeru ("continue to do so") is fine.¹

Kageyama further subdivides syntactic V2 by complement structure into two groups: a "VP-complement" group ("-sokoneru 'miss,' -sobireru 'miss the chance,' -okureru 'be late,' -akiru 'become weary,' -tukeru 'be accustomed,' -kaneru 'hesitate'") and a "V'-complement" group ("-naosu 'do again,' -wasureru 'forget,' -oeru 'finish,' -tukusu 'exhaust, do thoroughly'"). Long-distance passivization is grammatical for the V' group but not the VP group.¹

Why the split matters for learners

The split predicts coinability. You can freely produce 食べ始める, 読み続ける, or 走り出す without dictionary support, because the V2 is a syntactic suffix.¹ You must memorise 取り組む or 引き受ける because the V1+V2 combination is lexically frozen.¹³

The split also explains the asymmetry of dictionary coverage. The NINJAL lexicon enters 取り組む but does not enter every well-formed V-始める, because the syntactic family is rule-governed and not listed.³

Nuance and usage contexts

Aspectual V2: phase of action

The core syntactic aspectual members named in Kageyama's type B list are ～始める (begin), ～終える (finish, volitional transitive), ～続ける (continue), and ～出す (sudden onset).¹ Aspectual means that the V2 marks the phase or extent of an action. Additional members frequently treated as syntactic include ～切る (do completely / exhaustively), ～通す (do all the way through), ～尽くす (exhaust), and ～過ぎる (excess).¹

The ～始める / ～出す contrast is one of volition and control. "～始める generally denotes the start of an event, and although the agent of the action may have volition (willpower) over its execution... ～出す [features] a notable lack of control, which causes it to be ungrammatical with modal endings such as ～ていい."⁸ The direct contrast is 食べ始めてください (○) versus *食べ出してください (×).⁸

雨あめが降ふり出だした。⁵
"It started raining."

話はなし続つづける。¹
"I keep speaking."

アイスクリームが食たべきれない。⁹
"I can't finish eating the ice cream."

Directional and spatial V2

～込む is documented as "probably the most productive second verb." It works across four patterns: a non-inward action becomes inward, an already-inward action gets deeper, an action is enriched and intensified, or an action repeats until satisfaction.¹⁰⁵ Other directional V2 in this family include ～出す (out of), ～上げる / ～下げる (up / down), and ～回る (around). Each combines with a wide range of V1.

みんなでプールに飛とび込こんだ。¹⁰
"We all jumped into the pool together."

この靴くつ、かなり履はき込こんだからボロボロになってしまった。¹⁰
"I've worn these shoes a lot, so they've ended up tattered."

Manner and effort V2

～直す ("doing something again or redoing it") and ～過ぎる ("excess") are listed by Kageyama and confirmed in tutorial treatments.¹⁵ ～損なう / ～損ねる ("fail to") and ～慣れる ("get used to doing") are also documented as syntactic V2.¹ Each contributes a manner, effort, or modal flavour to the action rather than a direction.

夕食ゆうしょくを食たべ損そこねた。¹
"I missed eating dinner."

スープを温あたため直なおした。¹
"I reheated the soup."

Register and frequency

Compound verbs are register-neutral. The NINJAL lexicon catalogues them as the common stock of contemporary Japanese without genre restrictions. That means you meet them in news, novels, conversation, and business writing alike.³ The compound construction itself has no fixed politeness or formality implication. Politeness is realised on V2's inflection (飛び込みます vs 飛び込む).¹

Reading aids and ambiguity

Telling a compound verb apart from a te-form chain

食べ始める is one phonological word with no て between V1 and V2. Focus particles cannot intrude between the two verbs on the compound-verb reading.¹ In contrast, 食べて始める is two predicates linked by the te-form connective. Each verb allows independent inflection.¹

Structure	Form	Reading
Compound verb	食べ始める	one word, "begin to eat"
te-form chain	食べて始める	two verbs, "eat and then start (something else)"

Telling a compound verb apart from a noun + suru verb

Compound verbs use V1-stem + V2 (for example 飛び込む = the stem 飛び plus the verb 込む). Suru-verbs use 名詞 + する (for example 勉強する, a noun plus する). Kageyama treats V-V and VN+suru as distinct phenomena in separate chapters of his word-formation typology.¹

One diagnostic is that a true V-V compound rejects VN+suru in the V1 slot. For example, *toonyuu-si-komu "throw-do-insert" is ungrammatical, in contrast with the lexical compound 投げ込む nage-komu.¹

Stem-as-noun ambiguity

The ren'yōkei serves both as the input to compound-verb formation and as a deverbal noun (読み "reading," 始め "beginning").² Context tells you which use you are seeing. Nominal use takes nominal modifiers (本の読み "the reading of the book"), while compound-verb use takes V2 directly (読み始める).

Spot the stem-noun in a flash

If a particle follows the stem (の, が, を, は), the stem is acting as a noun. If a verb in dictionary form follows, the stem is feeding a compound.²

Looking up compound verbs

For unfamiliar V-V pairs, the NINJAL 複合動詞レキシコン (https://vvlexicon.ninjal.ac.jp) lists lexical compounds and classifies them by word structure and transitivity. It also links to contemporary written-language examples for each entry.³⁴ Syntactic compounds are not catalogued there because they are productively coinable.³ General dictionaries usually list the lexicalised compounds and skip the predictable ones, which mirrors the same split.

Good to know

Conjugating V1 instead of V2

If you treat V1 as the inflecting half, you might write *飛んだ込む for "jumped in." V1 is frozen in its ren'yōkei form. Tense, polarity, politeness, and te-form all attach to V2 only.¹ The intended sentence is:

飛とび込こんだ。⁶
"I jumped in."

Using 始まる where 始める belongs

A common error is *雨が降り始まった for "it started raining." The compound-verb V2 is 始める (the transitive auxiliary), not 始まる (intransitive). As Imabi puts it, "whether the main verb is transitive or not, the original transitivity of V2 is irrelevant, which means 始まる (the intransitive form) is never used in this capacity."⁸ The correct form is:

雨あめが降ふり始はじめた。⁸
"It started raining."

The same lockout does not extend cleanly to 終わる / 終える; both occur with different transitivity readings.⁸

～きれない is not the verb 切る "cut"

If you have met 切る "cut," you may misread 食べきれない as "cannot cut and eat." In compound-verb V2 use, ～切る is the completive aspectual suffix. ～きれない is its negative potential form meaning "cannot finish (doing)."⁹ The kanji surface of 食べきれない can be written 食べ切れない. It shares the character with 切る "to cut" but functions as the aspectual suffix in this position.⁹

アイスクリームが食たべきれない。⁹
"I can't finish eating the ice cream."

Productive coinage with syntactic V2

Type B (syntactic) V2 like ～始める, ～続ける, ～終える, ～出す, ～切る, and ～直す attach freely to any compatible V1. They form well in conversation, fiction, and academic prose.¹ Type A (lexical) pairings like 取り組む or 引き受ける are lexicalised. Coining a new type-A compound is not productive and will sound ill-formed.¹³

Bleached V2 and boundary cases

A few "compound-looking" verbs sit on the boundary of productive V-V. Their V2 has bleached into something closer to a prefix or suffix. Kageyama notes "exceptions" to the Transitivity Harmony Principle "whose first members appear to have turned into prefixes because of 'semantic bleaching,' or whose second members have almost become suffixes like -komu 'go in.'"¹ When in doubt, treat such items as single dictionary entries rather than as transparent V-V compounds.

Kanji choice in compound verbs

The V1 stem in a compound is often written in kanji even when the same stem as a standalone noun would be hiragana. This is a stylistic norm in established compounds, not a hard rule. It explains the consistent kanji surface of forms like 飛び込む, 取り組む, or 読み始める.³

See also

• ～始める, ～終わる, ～続ける in Japanese: Beginning, Ending, and Continuing an Action
• ～出す, ～切る, ～込む, ～直す in Japanese: V2 Aspect Suffixes (Sudden Onset, Completion, Inward/Depth, Redo)
• The Japanese Verb Stem (連用形): The Masu-Stem and Its Uses
• Japanese Verb Groups: 一段, 五段, and Irregular
• Transitivity Pairs in Japanese (自他動詞): Intransitive vs. Transitive
• The Masu Form (ます): Polite Present and Future Tense

References

Footnotes

1. Kageyama, Taro. "Word Formation." In The Handbook of Japanese Linguistics, edited by Natsuko Tsujimura, 297–325. Blackwell, 1999. https://www.blackwellpublishing.com/content/BPL_Images/content_store/WWW_Content/9780631234944/010.pdf ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹ ↩²² ↩²³ ↩²⁴ ↩²⁵ ↩²⁶ ↩²⁷ ↩²⁸ ↩²⁹ ↩³⁰ ↩³¹ ↩³² ↩³³ ↩³⁴ ↩³⁵ ↩³⁶ ↩³⁷ ↩³⁸ ↩³⁹ ↩⁴⁰ ↩⁴¹ ↩⁴² ↩⁴³ ↩⁴⁴ ↩⁴⁵ ↩⁴⁶

2. Wiktionary contributors. "連用形." Wiktionary. https://en.wiktionary.org/wiki/%E9%80%A3%E7%94%A8%E5%BD%A2 ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

3. 国立国語研究所. Compound Verb Lexicon (複合動詞レキシコン). Project leader: Taro Kageyama. https://vvlexicon.ninjal.ac.jp/en/ ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²

4. National Institutes for the Humanities. Compound Verb Lexicon resource guide entry. https://guides2.nihu.jp/resources/759 ↩ ↩²

5. Migaku. "Japanese Compound Verbs: How They Work and Common Patterns." https://migaku.com/blog/japanese/japanese-compound-verbs (limitation) ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

6. Wiktionary contributors. "飛び込む." Wiktionary. https://en.wiktionary.org/wiki/%E9%A3%9B%E3%81%B3%E8%BE%BC%E3%82%80 ↩ ↩² ↩³ ↩⁴

7. Wikipedia contributors. "Rendaku." Wikipedia. https://en.wikipedia.org/wiki/Rendaku ↩ ↩² ↩³ ↩⁴

8. Imabi. "Start to I: ～始める & ～出す." https://imabi.org/start-to-%EF%BD%9E%E5%A7%8B%E3%82%81%E3%82%8B-%EF%BD%9E%E5%87%BA%E3%81%99-%EF%BD%9E%E3%81%8B%E3%81%91%E3%82%8B/ (limitation) ↩ ↩² ↩³ ↩⁴ ↩⁵

9. Maggie Sensei. "V + きれない (= kirenai) & V + きる (= kiru)." https://maggiesensei.com/2013/08/22/v-%E3%81%8D%E3%82%8C%E3%81%AA%E3%81%84-kirenai-v-%E3%81%8D%E3%82%8Bkiru/ (limitation) ↩ ↩² ↩³ ↩⁴

10. Tofugu. "KOMU 込む Compound Verbs in Japanese (and How to Use Them)." https://www.tofugu.com/japanese/komu-compound-verbs/ (limitation) ↩ ↩² ↩³