The Japanese verb する (Suru) is one of the most important and versatile verbs in the language. It is an irregular verb that primarily means “to do” or “to make,” but it is also used in compound verbs, turning nouns into actions, and forming grammatical expressions.
Because of its many applications, mastering する is essential for anyone learning Japanese.
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Fundamentals of する
Unlike Ichidan and Godan verbs, する is irregular, meaning it does not follow standard conjugation rules. However, its conjugations are straightforward once you memorize them.
する as a Standalone Verb
In its simplest form, する means “to do” or “to make.”
At its core, する means “to do” or “to make,” and it’s incredibly versatile. When used by itself, it functions similarly to how “do” works in English.
For instance, in English, you might say something like “I’ll do this” or “I’ll do that,” where the word “do” refers to an action, but the specific nature of that action is not specified. In Japanese, する is used in a similar fashion to convey the idea of doing or making something happen.
Example Sentences:
これにする。
Kore ni suru.
"I’ll do this." (I’ll make this [my choice].)
それにする。
Kore ni suru.
"I’ll do that." (I’ll make that [my choice].)In these examples, する is attached to the noun (これ and それ) to indicate a decision or action without specifying exactly what action is being taken. It’s a simple and effective way of expressing intent or choice.
Noun + する to Turn Nouns into Verbs
One of the most useful applications of する is in its ability to convert nouns into verbs.
By adding する to a noun, you can create a verb that means “to do [something]”. This form is particularly common with abstract nouns, especially those of Chinese origin, known as Sino-Japanese words. These combinations are often referred to as “suru verbs” and are foundational in many areas of Japanese, from everyday conversation to more formal contexts.
Examples:
宿題 (shukudai) - "homework"
宿題する (shukudai suru) – "to do homework"
旅行 (ryokou) - "travel"
旅行する (ryokou suru) – "to travel"
会話 (kaiwa) "conversation"
会話する (kaiwa suru) – "to have a conversation"Example Sentences:
毎日、日本語の勉強をする。
(Mainichi, Nihongo no benkyou o suru.)
"I study Japanese every day."
週末に旅行するつもりです。
(Shuumatsu ni ryokou suru tsumori desu.)
"I plan to travel on the weekend."
彼女と会話するのは楽しい。
(Kanojo to kaiwa suru no wa tanoshii.)
"Having conversations with her is fun."These sentences demonstrate the flexibility of する, turning simple nouns into verbs that express everyday actions.
Adjective + する for Making Something “Adjective”
Another interesting feature of する is its ability to be used in combination with adjectives to express the action of making something happen in a certain way.
When paired with adjectives, する indicates that you are taking action to change or influence the state of something to match the adjective.
Examples:
静かにする
(shizuka ni suru)
"to make it quiet"
早くする
(hayaku suru)
"to make it fast"
部屋をきれいにする
(heya o kirei ni suru)
"to make the room clean"Example Sentences:
子供たちに静かにするように言った。
(Kodomo-tachi ni shizuka ni suru you ni itta.)
"I told the children to be quiet."
もっと早くする必要があります。
(Motto hayaku suru hitsuyou ga arimasu.)
"We need to make it faster."
部屋をきれいにした。
(Heya o kirei ni shita.)
"I cleaned the room."Conjugation of する
Since する is an irregular verb, its conjugation does not follow standard rules. Here is a breakdown of its various forms:
Present Tense – する/します
The dictionary form is する, the polite form to changes する to します.
Casual (する)
彼は毎日運動する。
(Kare wa mainichi undou suru.)
"He exercises every day."
Polite (します)
仕事をします。
(Shigoto o shimasu.)
"I will work."Present Negative – しない / しません
To make する negative, use しない in casual speech and しません in polite speech.
Casual (しない)
宿題をしない。
(Shukudai o shinai.)
"I won’t do my homework."
Polite (しません)
宿題をしません。
(Shukudai o shimasen.)
"I won’t do my homework."Past Tense – した / しました
To express the past tense, する changes to した in casual speech and しました in polite speech.
Casual (した)
昨日、運動した。
(Kinou, undou shita.)
"I exercised yesterday."
Polite (しました)
昨日、運動しました。
(Kinou, undou shimashita.)
"I exercised yesterday."Past Negative – しなかった / しませんでした
To express past negative, する changes to しなかった in casual speech and しませんでした in polite speech.
Casual (しなかった)
運動をしなかった。
(Undou o shinakatta.)
"I didn’t exercise."
Polite (しませんでした)
運動をしませんでした。
(Undou o shimasen deshita.)
"I didn’t exercise."する Variations
In addition to its fundamental uses, する can be paired with different particles or expressions to create a wide variety of meanings. These variations allow for nuanced expression, ranging from sensory experiences to decision-making and assumptions.
にする (ni suru) – “To decide on” / “To make (something) into”
When する is combined with に, it often expresses the act of deciding or choosing something. It can also indicate changing something into a particular state or form.
Examples
昼ご飯はラーメンにする。
(Hirugohan wa rāmen ni suru.)
"I’ll have ramen for lunch."
部屋をきれいにする。
(Heya o kirei ni suru.)
"I will make the room clean."When referring to decisions, にする is more active than になる, which is used to express something naturally becoming a state. The focus here is on taking deliberate action or making a choice.
がする (ga suru) – “To sense something” (smell, sound, taste, feeling)
This pattern is used to describe sensory experiences, such as perceiving a smell, sound, taste, or physical sensation.
Examples
いい匂いがする。
Ii nioi ga suru.
"It smells good."
変な音がする。
Hen na oto ga suru.
"I hear a strange sound."
甘い味がする。
Amai aji ga suru.
"It tastes sweet."
寒気がする。
Samuke ga suru.
"I feel a chill."This construction is often used to express something perceived indirectly by the senses, rather than directly experiencing the object itself.
をする (o suru) – “To do (something)”
This common structure is used with nouns to describe performing an action or engaging in an activity. Many everyday activities are expressed in this form.
Examples
勉強をする。
Benkyō o suru.
"To study."
買い物をする。
Kaimono o suru.
"To go shopping."
スポーツをする。
Supōtsu o suru.
"To play sports."This is used mainly to pair with nouns. But you can omit the を in most cases as it is automatically inferred in context.
とする (to suru) – “To try to (do something)” / “To assume (something)”
とする has two major uses depending on whether you’re using it together with a noun or verb.
If you are using it together with a verb, then it implies you are trying to perform that action.
If you are using it together with a noun, it applies that the object is assuming that noun.
Example (Trying to do something)
寝ようとする。
(Neyō to suru.)
"To try to sleep."
彼はドアを開けようとした。
(Kare wa doa o akeyō to shita.)
"He tried to open the door."Example (Assuming a state)
Assuming something as a state:
彼を犯人とする。
(Kare o hannin to suru.) → "To consider him the criminal."にしては (ni shite wa) – “Considering (something), it is…”
にしては is used to express an unexpected outcome or contrast between what was expected and what actually happened. This phrase often conveys surprise or disbelief.
Examples
彼は初心者にしては上手だ。
(Kare wa shoshinsha ni shite wa jōzu da.)
"Considering he’s a beginner, he’s pretty good."
日本人にしては漢字が苦手だ。
(Nihonjin ni shite wa kanji ga nigate da.)
"Considering he’s Japanese, he’s bad at kanji."This construction highlights an unexpected outcome, often signaling surprise, especially when reality defies expectations.
にしても (ni shite mo) – “Even if” / “Even considering…”
にしても is used to express contrast or a concession. It acknowledges a fact but introduces a different perspective or conclusion.
Examples
負けたにしても、よく頑張ったよ。
(Maketa ni shite mo, yoku ganbatta yo.)
"Even if we lost, we still did our best."
寒いにしても、コートは必要ないよ。
(Samui ni shite mo, kōto wa hitsuyō nai yo.)
"Even if it's cold, you don’t need a coat."This pattern emphasizes a contrasting statement or decision despite an acknowledged fact.
にして (ni shite) – “As (someone/something), in the role of…”
This structure highlights someone’s role or position, emphasizing their behavior or characteristics in that role. It is commonly used when showing contrast between what’s expected in a role and the reality of the person or thing in that role.
Examples
彼はプロにしては優しすぎる。
(Kare wa puro ni shite wa yasashi sugiru.)
"For a pro, he’s too kind."
大統領にして、国民の人気がない。
(Daitōryō ni shite, kokumin no ninki ga nai.)
"As a president, he’s unpopular."Often used to show surprising or contrasting characteristics in someone’s role or status.
ことにする (koto ni suru) – “To decide to (do something)”
This form indicates a decision made by the speaker to do something. It can also express a personal decision, and when used in the past form, it shows that the decision has already been made.
Examples
毎朝早く起きることにする。
(Maiasa hayaku okiru koto ni suru.)
"I’ve decided to wake up early every morning."
運動することにした。
(Undō suru koto ni shita.)
"I decided to exercise."The past form ことにした indicates a decision already made, while ことにしている refers to a decision that has become a routine or habit.