Nouns → Verbs with する
Numerous verbs are made with する attached to nouns. する is primarily seen after 漢語名詞, nouns that are Sino-Japanese (Chinese based) in origin or composition. However, する is not limited to these nouns. It is also seen after native words and recent loanwords.
| To study | 勉強する | To buy and sell | 売買する |
| To eat and drink | 飲食する | To point out | 指図する |
| To oversleep | 寝坊する | To exchange (money) | 両替する |
| To love (sexual relation) | 恋する | To sweat | 汗する |
| To copy | コピーする | To sign | サインする |
| To design | デザインする | To cancel | キャンセルする |
Creating a verb out of a noun with する may simple, but there are a lot of strange semantic restrictions that have to be examined. For instance, even though 供給 (supply) is the opposite of 需要 (demand), only 供給 can be followed by する. This lesson will investigate what exactly the patterns are to figuring this out.
Particles are also confusing. Some nouns become verbalized by adding ～する, ～をする, ～にする, ～になる, a combination of these. This does not consider the particle to be used before the resultant verb phrase.
Initial Problems
Our first problem is when to use ～をする as opposed to just attaching する directly to the noun in question. From the very beginning of your Japanese studies, you’ve likely encountered very basic vocabulary in which this を is optional: 練習（を）する (to practice ) and 勉強（を）する (to study).
Extending ～をする haphazardly to any する verb isn’t correct, however, as there are situations in which only ～する or ～をする is right. There are even nouns that require completely different means to be turned into a verb.
| To play tennis | テニス｛をする 〇・する △｝ | To play baseball | 野球｛をする 〇 ・する △｝ |
| To mean/imply | 意味｛する 〇・をする X｝ | To connotate | 含意｛する 〇・をする X｝ |
| To consult | 参考｛する X・をする X・にする 〇｝ | To be in a daze | 夢中｛する X ・をする X・になる 〇｝ |
Clarification Notes:
1. 意味をする may be used if you have ～という意味 or ～のような意味. However, the verb 意味する is not quite the same as just to define. Rather, it is more like “to imply.”
2. Particle omission is a common practice in casual speech, but in non-casual speech, expressions like テニスする become improper.
When the particle を is required, する is interpreted literally. This する is sometimes called a 重動詞 (heavy verb) in contrast to when it is just a grammatical item. Notice that the words that only take をする are specific activities: 強盗, テニス, 野球. Are these nouns then made verbs? No, they’re obligatorily marked by を and are thus functioning as direct objects.
For activity nouns that are broad in meaning such as 勉強 and 練習, we see that を is optional. When を is used, these nouns usually have some sort of attribute, making them more specific.
1. 日本語の勉強をする。
To study Japanese.
Literally: To do Japanese studies.
For those that obligatorily only take する, they all represent a state/situation. More examples of these nouns include 刺殺 (stabbing to death), 集中 (concentration), 信用 (trust), 逆転 (reversal).
When する cannot be used at all, the noun lacks a strong verbal aspect. Ignoring set phrases that may break the rules, there are a set of tests to determine whether a noun has a high enough 動詞性 (verbal nature) to take する.
する or not to する
Test 1: Aspect Modifier Test
Time phrases like “until” (までに) in Japanese set aspect limitations on verbs. Aspect is the grammatical concept that denotes how a verb behaves over a duration of time. If a noun in Japanese can take a time parameter setting phrase such as までに, then it is said to have a high 動詞性, which means it should also have a verb form that can take those same time phrases.
2a. 明日までの仕上がり （Noun Phrase) 2b. 明日までに仕上がる （Verb Phrase)
Completion by tomorrow To complete by tomorrow
If you were to replace 仕上がり with 本 or 部屋, which are both Sino-Japanese nouns, you do not get a valid sentence. These physical objects have nothing to do with time. Likewise, even if a noun can be about a state that may occur over a period of time, if a time parameter is not built into its meaning, producing a valid noun phrase like in 2a. will reversely be impossible.
3a. 夜以内の痛み X 3b. 夜の痛み 〇 3c. 夜に痛む
～以内 creates a time parameter in the same way the particle までに does. In this example, we see that 痛む (to hurt/ache) does have a noun form (痛み), but it doesn’t make sense to say “pain within the night” as pain is not recognized as having a definitive end point.
Applying this information to する verbs, when you have a Sino-Japanese noun that can take a time parameter phrase such as までに, する can be used with it. If the noun cannot, you may still have ～をする in which the time phrase agrees with the literal definition of する.
| Nominal Phrase | Verbal Phrase | ＋する? |
| 完了 (Completion) | 完了する (To complete) | 〇 |
| 完成 (Completion) | 完成する (To complete/perfect) | 〇 |
| 計算 (Calculation) | 計算する (To calculate) | 〇 |
| 算数 (Arithmetic) | 算数をする (To do arithmetic) | X/△ |
As you can see, neither language allows “to arithmetic” because math is always a part of our world without a deadline. Although you may still hear 算数する due to casual omission of the particle を, that must be treated as a separate phenomenon.
Test 2: Aspect Ending Test
Nouns that describe a コト (event) and can be followed by time endings such as ～後 (after) ～中 (under/during) should have verb forms.
| 採用 | Adoption (of something) | 活動 | Activity |
| 研究 | Research | 募集 | Recruitment |
| 建設 | Construction | 仮眠 | Doze |
All these nouns can take する, and because they are all examples of activities, attaching をする to these nouns is also valid. When nouns cannot take endings such as ～後 or ～中, then you should expect them not to take する. Such nouns include 感動 (feeling/movement), 緊張 (nervousness), 静止 (stillness), 信用 (trust/faith), 信頼. They express particular states that can’t be viewed as having exact beginnings, midpoints, or ends.
Test 3: State Aspect Test
Nouns that represent states that may change over time are more verb-like. When we use 一時的な (temporary), we can quickly eliminate many nouns that can’t take する.
4. 一時的な｛緊張 〇 (Nervousness)・保存 (Preservation) 〇・在庫 (Stock (supply)) 〇/△・健康 (health) X・精神 (spirit/mind) X｝
Words like 健康 and 精神 also fail previous aspect tenses. They have no salient relation with time. Although nouns like 緊張, 混乱 (chaos), and 流行 (fashion/trend) may not necessarily have defined time frames, these stages are subject to change, and change takes time.
Note: As for 在庫（を）する, the noun 在庫 means “stock/inventory.” In business, doing inventory is very important, and as it is such an integral part of business, the noun 在庫 has been re-purposed to be used as a noun, even though it is viewed as a physical noun otherwise–one that does happen to change over time. Usually, being a concrete noun like 本 (book), 熱 (fever), 病院 (hospital) would negate this test even if the noun’s state is subject to change.
Test 4: Intent/State of Action with Adjective Modifiers Test
There are still some する verbs not accounted for. For nouns with which intention and state can be expressed with an adjectival modifier, it is more verb-like and should take する. Those that can’t show intention in this way are less verb-like and shouldn’t take する.
For instance, 夢中 literally means “within a daze.” It does describe a state, but it does not take する because there is no intent on the part of the doer. This is also why 需要 doesn’t have a する verb form.
Final Comments
With these four tests, you should be able to correctly assume whether a noun can take する or not. Beware of influence from your native language(s) that may make you accidentally say things like 独立になる, which should be 独立する (to become independent). Independence like marriage presumably lasts for some time. 独立 along with 結婚, 安心, etc. pass Test 3 and thus have する verbs. If a noun fails this test, ～になる, ～にする, or both might be used instead.
As final examples, consider 瀕死 (to become moribund) and 中毒 (intoxication/poisoning). 瀕死する fails all tests. When verbal, you say 瀕死になる, as expected. Both 瀕死 and 中毒 don’t make sense with “temporary”. They describe things that simply happen/come to be. It would be weird to say that something was moribund for several days or someone was intoxicated for two hours.
Word Note: 中毒する does exist in the transitive sense of “to poison”, which then passes Test 4.
Particle Note: The particle used before the する verb is determined by the semantics of the verb phrase itself. This is not the topic of this lesson. The topic of this lesson is what sort of nouns become する verbs and which ones need を.
For instance, を敬礼する is ungrammatical because the する verb 敬礼する means “to salute”, and because you “salute to something”, you use the particle に with it. Though not using “to” is alright in English, this is not English, so you are going to have to consider how 敬礼する is used and not assume it’s like its English equivalents.
Examples
After a long time studying grammar, we will end this section with example sentences with even more する verbs. Though not part of the exercises, try to figure out which tests these verbs passed to be acceptable.
5. 今晩、予約したスミスです。
I am Smith with a reservation for tonight.
6. 日本に留学します。
I will study abroad in Japan.
7. 会議を休止する。
To adjourn/pause a meeting.
8. 会う約束をキャンセルする。
To cancel an appointment.
Different Kinds of する Verbs
Long time ago, する was す. After certain words, it was voiced as ず, which changed to the interchangeable ～じる・ずる that differ only in speech style and conjugation. The tests taught in this lesson still work for these verbs. Only their conjugations are tricky.
～ずる came before ～じる, but the latter is more common. ～ずる is mainly found in literature, but because they do occasionally show up, you at least need to know that you are looking at a form of する and that it has a more modern equivalent, ～じる.
| みぜんけい | れんようけい | しゅうしけい | れんたいけい | いぜんけい | めいれいけい | |
| ～じる | じ- | じ- | じる | じる- | じれ- | じろ・じよ |
| ～ずる | ぜ・じ- | じ- | ず（る） | ずる- | ずれ- | ぜよ |
Base Note: Like する, ぜ is used with older endings. So, you don’t need to know it now.
Another sound change with する occurs when it attaches to single character Sino-Japanese nouns that end in つ. This つ, then, subsequently contracts to っ. The chart below illustrates the bases of 発する (to emit).
| 動詞 | みぜんけい | れんようけい | しゅうしけい | れんたいけい | いぜんけい | めいれいけい |
| 発する | 発し・発せ・発さ- | 発し- | 発す（る） | 発する- | 発すれ- | しろ・せよ |
Base Note: し- takes ～ない and the volitional as expected, but さ- can also take ～ない aside from being used with the passive and causative. せ-, is of course used with older endings that you should not worry about at this point. It’s just that if you see する verbs in these forms and see that the vowel in the base has changed to an “e”, you at least know what base you’re looking at. This alone can help you know what the ending is being used for.
More Examples
| To emit | 発する | To presume | 察する | To believe | 信｛じる・ずる｝ |
| To feel; sense | 感｛じる・ずる｝ | To anticipate | 先ん｛じる・ずる｝ | To value | 重ん｛じる・ずる｝ |
| To memorize | 諳ん｛じる・ずる｝ |
Word Note: Notice that じる・ずる do not only follow Sino-Japanese words. When following native words, the native root is followed by ん, which then じる・ずる follows.