Japanese verb conjugation, explained
Japanese verbs are far more regular than English ones: there are three groups, and two of the three have exactly two members. Learn which group a verb is in and every form follows from a short list of rules.
Group 2 — Ichidan (ru-verbs)
The easy group. The dictionary form always ends in -iru or -eru (たべる, みる, おぼえる). To conjugate, delete る and attach the ending — nothing inside the word ever changes.
Warning: ending in -iru/-eru does not guarantee ichidan. 帰る (kaeru, “to go home”), 走る (hashiru), 入る (hairu), 切る (kiru) and 知る (shiru) look like ru-verbs but conjugate as godan. Those you memorise.
Group 1 — Godan (u-verbs)
Everything else that ends in an u-sound: う く ぐ す つ ぬ ぶ む る. The final kana slides up and down its column of the kana chart — that is what “godan”, five rows, means. 書く → 書かない, 書きます, 書けば, 書こう.
The one genuinely fiddly part is the te-form, which depends on the last kana: う・つ・る → って, ぬ・ぶ・む → んで, く → いて, ぐ → いで, す → して. 行く is the famous exception: 行って, not 行いて.
Group 3 — Irregular
There are only two, and every learner meets them on day one: する (to do) and 来る (to come). する is also how Japanese turns nouns into verbs — 勉強する, 料理する, 電話する — so learning its forms unlocks hundreds of verbs at once.
来る is irregular in its reading rather than its spelling: the kanji 来 stays put while the sound moves こ / き / く (来ない konai, 来ます kimasu, 来れば kureba).
How to tell which group a verb is in
- Does it end in something other than る? → godan. Done.
- Does it end in る with an a/u/o sound before it (かる, ぐる, のる)? → godan.
- Does it end in -iru or -eru? → usually ichidan, but check it against the exception list above.
- Is it する or 来る (or a noun + する)? → irregular.
What each form is for
| Form | Use |
|---|---|
| Dictionary / plain | The form you look up. Also the casual present and future. |
| Plain negative | “doesn’t / won’t”. From here it conjugates like an i-adjective. |
| Plain past | The casual past — same ending as the te-form, with た/だ. |
| Plain past negative | “didn’t”. The negative past, still i-adjective-shaped. |
| Te-form | The connector: requests, linking clauses, ~ている. |
| Progressive (~ている) | “is ~ing”, or an ongoing resulting state. |
| Desire (~たい) | “want to ~”. Behaves as an i-adjective. |
| Volitional | “let’s ~” / “I think I’ll ~”. |
| Potential | “can ~”. What you could do; the object often takes が. |
| Passive | “is ~ed”. Also the honorific and the suffering passive. |
| Causative | Make or let someone do it. |
| Causative-passive | Be made to do it — the long one. |
| Imperative | Blunt order. Use ~てください in real life. |
| Prohibitive | “don’t!” — dictionary form + な. |
| Conditional (~ば) | “if ~”. General rules and hypotheticals. |
| Conditional (~たら) | “if / when ~”. The everyday conditional. |
Practise on a real verb
Pick any verb and see all sixteen forms side by side, with audio: 食べる, 書く, 行く, する or 来る. Or browse the N5 verb list to start from the beginning.