する (suru) conjugation
to do, to attempt
する (する, suru) is an irregular verb. Only する and 来る are truly irregular, and every learner meets them in week one. Every form below is tappable — hear it, then say it back.
Written 為る in kanji, but usually written in kana alone.
Conjugation table
| Form | Plain (casual) | Polite (~ます) | When you use it |
|---|---|---|---|
| Dictionary / plain | する suru | します shimasu | The form you look up. Also the casual present and future. |
| Plain negative | しない shinai | しません shimasen | “doesn’t / won’t”. From here it conjugates like an i-adjective. |
| Plain past | した shita | しました shimashita | The casual past — same ending as the te-form, with た/だ. |
| Plain past negative | しなかった shinakatta | しませんでした shimasendeshita | “didn’t”. The negative past, still i-adjective-shaped. |
| Te-form | して shite | — | The connector: requests, linking clauses, ~ている. |
| Progressive (~ている) | している shiteiru | しています shiteimasu | “is ~ing”, or an ongoing resulting state. |
| Desire (~たい) | したい shitai | したいです shitaidesu | “want to ~”. Behaves as an i-adjective. |
| Volitional | しよう shiyou | しましょう shimashou | “let’s ~” / “I think I’ll ~”. |
| Potential | できる dekiru | できます dekimasu | “can ~”. What you could do; the object often takes が. |
| Passive | される sareru | されます saremasu | “is ~ed”. Also the honorific and the suffering passive. |
| Causative | させる saseru | させます sasemasu | Make or let someone do it. |
| Causative-passive | させられる saserareru | させられます saseraremasu | Be made to do it — the long one. |
| Imperative | しろ shiro | してください shitekudasai | Blunt order. Use ~てください in real life. |
| Prohibitive | するな suruna | — | “don’t!” — dictionary form + な. |
| Conditional (~ば) | すれば sureba | — | “if ~”. General rules and hypotheticals. |
| Conditional (~たら) | したら shitara | — | “if / when ~”. The everyday conditional. |
🔊 Tap any Japanese word to hear it spoken.
Why it conjugates this way
Only する and 来る are truly irregular, and every learner meets them in week one.
See the full rules on the verb conjugation guide.