Suru Verbs

Definition:

Suru verbs are Japanese verbs formed by combining a noun (most commonly a Sino-Japanese kango compound) with the verb suru (する), meaning “to do.” The resulting construction functions as a single verb meaning “to do [noun].” This is one of the most productive patterns in Japanese grammar — it instantly converts thousands of kanji-based nouns into action verbs.

How Suru Verbs Work

The basic pattern is:

> [Noun/Compound] + する = Verb

Why This Matters for Learners

Learning that [noun] + suru = verb for Sino-Japanese compounds is one of the highest-leverage patterns in Japanese:

1. Vocabulary multiplier: Every new kango compound potentially becomes both a noun AND a verb
2. Decoding power: Even if you’ve never heard a -suru verb before, knowing the noun root lets you understand the verb
3. Production strategy: When you don’t know the precise Japanese verb, composing [noun] + suru often gives a natural result
4. JLPT application: A large proportion of N3–N1 vocabulary items are suru-verb compounds

Conjugation of Suru Verbs

Suru verbs conjugate exactly like the irregular verb suru (する), regardless of the noun root. This means:

Using benkyō suru (勉強する, to study) as example:

Key irregular forms of suru itself:

• shi- is the masu-stem (not sur-)
• Negative: shinai (not suranai)
• Potential: dekiru (a completely separate word — “can do”)
• Passive/Causative: sareru / saseru

Suru vs. the Noun Alone

Many suru-verb nouns can be used as just nouns, or in a wo suru (をする) construction with the object marker:

In modern spoken Japanese, dropping wo is extremely common: benkyō suru is more natural in most contexts than benkyō wo suru.

Types of Suru Verb Sources

Sino-Japanese (kango) compounds — most common:

• 電話する (denwa suru) — to telephone
• 心配する (shinpai suru) — to worry
• 注意する (chūi suru) — to be careful / to warn
• 失敗する (shippai suru) — to fail
• 成功する (seikō suru) — to succeed
• 理解する (rikai suru) — to understand
• 調査する (chōsa suru) — to investigate

Loanwords (gairaigo) — highly productive:

Adding suru to katakana loan nouns is extremely productive in modern Japanese:

• コピーする (kopī suru) — to copy
• チェックする (chekku suru) — to check
• サインする (sain suru) — to sign
• メモする (memo suru) — to take notes
• グーグルする (gūguru suru) — to Google
• インストールする (insutōru suru) — to install
• アップデートする (appudēto suru) — to update
• サーフィンする (sāfin suru) — to surf
• ダウンロードする (daunrōdo suru) — to download

This shows that suru remains a highly productive morphological tool for adapting new concepts to Japanese.

Native Japanese (wago) nouns with suru:

Less common, but some exist:

• びっくりする (bikkuri suru) — to be surprised (from mimetic word)
• のんきする (nonki suru) — to be easygoing
• がっかりする (gakkari suru) — to be disappointed (mimetic)

Suru as an Irregular Verb

Suru is one of only two fully irregular verbs in Japanese (the other being kuru, to come). Its forms don’t follow either godan or ichidan patterns:

• Dictionary: suru
• Masu-stem: shi (not sur)
• Negative: shinai (not suranai)
• Te-form: shite
• Past: shita
• Volitional: shiyō
• Imperative: shiro (informal) / nasai (formal)

History

する verbs (suru verbs) trace their origins to the incorporation of Sino-Japanese vocabulary into Japanese following the adoption of Chinese characters beginning in the 5th-6th centuries. As Chinese-origin nouns (漢語) entered Japanese, the native verb する (“to do”) was attached to create verbs from nominal concepts — a pattern that became one of Japanese’s most productive morphological processes. The pattern’s productivity has continued into modern Japanese, where it extends to Western loanwords (サボる from French “sabotage,” though this is irregular) and new coinages. The grammatical analysis of Sino-Japanese compound + する as a single lexical unit vs. a noun + light verb construction has been debated in Japanese linguistics since the mid-20th century.

Common Misconceptions

“Any noun can become a する verb.”

Only specific nouns — predominantly Sino-Japanese compounds — productively take する. Native Japanese (和語) nouns generally do not form する verbs (山する, 海する are ungrammatical). The pattern is semantically constrained: the noun must describe an action or process (勉強 “study,” 運動 “exercise”) rather than a concrete object.

“する verbs are always written as [noun]する.”

In many cases, the noun and する contract or the particle を intervenes: 勉強する (direct attachment) vs. 勉強をする (with を particle). Both forms are grammatical, with register and formality differences. Some combinations strongly prefer one form over the other.

“する verbs conjugate differently from other verbs.”

する itself is an irregular verb with a unique conjugation pattern (し-、し-、する、する、すれ-、しろ/せよ), but the irregularity is in する alone — learners need to master one conjugation pattern that then applies to all する verb compounds.

“Learning する verbs is not important because they’re just noun + do.”

する compounds make up a massive portion of adult Japanese vocabulary — academic, professional, and formal language relies heavily on Sino-Japanese する verbs. Ignoring them severely limits reading comprehension for intermediate and advanced texts.

Criticisms

The pedagogical treatment of する verbs has been criticized for underrepresenting their importance in Japanese language curricula. Many textbooks introduce する verbs as a minor verb type alongside ichidan and godan verbs, despite their enormous vocabulary coverage in formal and written Japanese.

Linguistic debate about the internal structure of する verbs — whether 勉強する is one word (a compound verb) or two words (a noun + light verb) — has practical implications for learners: the answer affects how these forms should be entered in dictionaries, parsed by learners, and analyzed in sentence mining. Neither analysis fully captures all the data, and different dictionaries and analysis tools handle する verbs inconsistently, creating confusion for learners using multiple resources.

Social Media Sentiment

する verbs are a standard discussion topic in Japanese learning communities. On Reddit (r/LearnJapanese), questions about when to use を with する compounds, which nouns can take する, and how する verb conjugation works appear regularly. Community explanations typically emphasize the pattern’s productivity and the importance of learning Sino-Japanese compound vocabulary.

The を vs. direct-attachment debate (勉強する vs. 勉強をする) generates recurring discussion threads, with native speaker input often confirming that both forms are natural but with context-dependent preferences.

Practical Application

For learners using Sakubo or Anki: when you encounter a new kango compound, immediately check if it can take suru. If it can, you’ve acquired both the noun and the corresponding verb simultaneously.

Study tip: Practice suru verbs in sentence frames rather than in isolation — the te-form and past tense arise in natural conversation constantly:

• benkyō shita — studied
• chekku shite kudasai — please check
• shinpai shinaide — don’t worry

Related Terms

• Godan Verbs — Type 1 verb class
• Ichidan Verbs — Type 2 verb class
• Verb Conjugation — complete verb system
• Japanese Particles — particles used with suru verbs
• Morphology — framework for analyzing verb formation
• Derivational Morphology — creating new words from existing morphemes

See Also

• Godan Verbs — Type 1 verb class
• Ichidan Verbs — Type 2 verb class
• Verb Conjugation — complete verb system
• Sakubo

Research

Research on する verb acquisition by L2 learners focuses on two areas: the productivity of the pattern (which nouns do learners correctly identify as する-eligible?) and the syntactic analysis (noun + する as one unit or two?). Miyagawa (1987) provided foundational analysis of the light verb する construction, influencing subsequent teaching approaches.

Acquisition research (Mori, 2002) suggests that learners who develop strong Sino-Japanese compound vocabulary knowledge (recognizing shared kanji components across compounds) more readily identify potential する verbs. The productivity of the pattern makes it a high-value target for vocabulary instruction: learning that a Sino-Japanese compound can take する effectively doubles the learner’s usable vocabulary for that concept (noun + verb). Tagashira (2011) investigated learner difficulties with する verbs, finding that the noun-verb boundary and particle selection (する vs. をする) were persistent error sources.