Japanese verbs fall into three conjugation classes: godan verbs (commonly called "u-verbs" or Group I), ichidan verbs (commonly called "ru-verbs" or Group II), and a small group of irregular verbs (Group III), which in practice is just する (suru, "to do") and 来る (kuru, "to come"). Unlike European languages, Japanese verb endings do not change for person or number - only for tense, aspect, mood, and politeness. One form covers "I eat," "you eat," "we eat," and "they eat." What varies is whether the verb is polite or plain, past or non-past, affirmative or negative, and what extended forms (potential, passive, causative, conditional, volitional) apply.
This reference lays out the full conjugation of one verb from each class through all the essential forms. For a beginner's first pass, see the Japanese verb conjugation beginners guide. For the particles that surround verbs, see the Japanese particles complete reference. For politeness levels that interact with verb forms, see the Japanese keigo honorific reference.
The Three Verb Classes
Table 1. Verb classes with sample verbs.
| Class | Common name | Dictionary ending pattern | Examples |
|---|---|---|---|
| Godan | u-verbs / Group I | Any -u (but not eru/iru with certain patterns) | 書く kaku, 話す hanasu, 飲む nomu, 読む yomu, 待つ matsu, 買う kau |
| Ichidan | ru-verbs / Group II | -eru or -iru (with specific stem patterns) | 食べる taberu, 見る miru, 起きる okiru, 寝る neru |
| Irregular | Group III | Only two verbs | する suru, 来る kuru |
Some verbs look like ichidan by ending but are actually godan. Common traps: 帰る kaeru (return), 走る hashiru (run), 入る hairu (enter), 切る kiru (cut), 知る shiru (know), 要る iru (need), 限る kagiru (limit), 喋る shaberu (chat). These are godan despite the -eru/-iru ending.
Godan (U-Verb) Conjugation
Take 書く (kaku, "to write") as the sample.
Table 2. 書く (kaku) in major forms.
| Form | Conjugation | Translation |
|---|---|---|
| Dictionary (plain non-past) | 書く kaku | write / will write |
| Polite non-past (masu-form) | 書きます kakimasu | write (polite) |
| Plain negative | 書かない kakanai | don't write |
| Polite negative | 書きません kakimasen | don't write (polite) |
| Plain past | 書いた kaita | wrote |
| Polite past | 書きました kakimashita | wrote (polite) |
| Plain negative past | 書かなかった kakanakatta | didn't write |
| Polite negative past | 書きませんでした kakimasen deshita | didn't write (polite) |
| Te-form | 書いて kaite | writing, and then writing |
| Potential | 書ける kakeru | can write |
| Passive | 書かれる kakareru | be written |
| Causative | 書かせる kakaseru | make/let write |
| Volitional plain | 書こう kakou | let's write |
| Volitional polite | 書きましょう kakimashou | let's write |
| Imperative plain | 書け kake | Write! |
| Conditional ba | 書けば kakeba | if [one] writes |
| Conditional tara | 書いたら kaitara | if [one] writes / when [one] wrote |
Godan te-form and ta-form rules
The te-form and ta-form of godan verbs depend on the final syllable:
Table 3. Te-form and ta-form rules for godan verbs.
| Dictionary ending | Te-form | Ta-form | Example |
|---|---|---|---|
| -u, -tsu, -ru | -tte | -tta | 会う - 会って - 会った |
| -mu, -bu, -nu | -nde | -nda | 読む - 読んで - 読んだ |
| -ku | -ite | -ita | 書く - 書いて - 書いた |
| -gu | -ide | -ida | 泳ぐ - 泳いで - 泳いだ |
| -su | -shite | -shita | 話す - 話して - 話した |
Exception: 行く (iku, "to go") has te-form 行って, not *行いて.
Ichidan (Ru-Verb) Conjugation
Ichidan verbs are simpler: drop the final る and add the ending. Take 食べる (taberu, "to eat").
Table 4. 食べる (taberu) in major forms.
| Form | Conjugation | Translation |
|---|---|---|
| Dictionary | 食べる taberu | eat |
| Polite non-past | 食べます tabemasu | eat (polite) |
| Plain negative | 食べない tabenai | don't eat |
| Polite negative | 食べません tabemasen | don't eat (polite) |
| Plain past | 食べた tabeta | ate |
| Polite past | 食べました tabemashita | ate (polite) |
| Plain negative past | 食べなかった tabenakatta | didn't eat |
| Polite negative past | 食べませんでした tabemasen deshita | didn't eat (polite) |
| Te-form | 食べて tabete | eating, and then eating |
| Potential | 食べられる taberareru | can eat |
| Passive | 食べられる taberareru | be eaten |
| Causative | 食べさせる tabesaseru | make/let eat |
| Volitional plain | 食べよう tabeyou | let's eat |
| Volitional polite | 食べましょう tabemashou | let's eat |
| Imperative plain | 食べろ tabero | Eat! |
| Conditional ba | 食べれば tabereba | if [one] eats |
| Conditional tara | 食べたら tabetara | if [one] eats / when [one] ate |
Notice that for ichidan verbs, potential and passive have the same form (-られる), which can be ambiguous. In colloquial Japanese, potential is often shortened to -れる (ra-nuki kotoba): 食べれる instead of 食べられる.
Irregular Verbs
Table 5. する (suru, "to do") conjugations.
| Form | Conjugation |
|---|---|
| Dictionary | する suru |
| Polite | します shimasu |
| Plain negative | しない shinai |
| Plain past | した shita |
| Plain neg past | しなかった shinakatta |
| Te-form | して shite |
| Potential | できる dekiru |
| Passive | される sareru |
| Causative | させる saseru |
| Volitional | しよう shiyou |
| Imperative | しろ shiro |
する joins many nouns to form verbs: 勉強する (benkyou suru, "to study"), 運動する (undou suru, "to exercise").
Table 6. 来る (kuru, "to come") conjugations.
| Form | Conjugation |
|---|---|
| Dictionary | 来る kuru |
| Polite | 来ます kimasu |
| Plain negative | 来ない konai |
| Plain past | 来た kita |
| Plain neg past | 来なかった konakatta |
| Te-form | 来て kite |
| Potential | 来られる korareru |
| Passive | 来られる korareru |
| Causative | 来させる kosaseru |
| Volitional | 来よう koyou |
| Imperative | 来い koi |
来る is particularly tricky because the stem changes vowel: く (ku) in dictionary form, き (ki) in polite form, こ (ko) in negative and causative.
Master Table: Sample Verb from Each Class
Table 7. Side-by-side conjugations.
| Form | 書く (godan) | 食べる (ichidan) | する (irreg) | 来る (irreg) |
|---|---|---|---|---|
| Dictionary | 書く | 食べる | する | 来る |
| Masu | 書きます | 食べます | します | 来ます |
| Plain neg | 書かない | 食べない | しない | 来ない |
| Past | 書いた | 食べた | した | 来た |
| Te | 書いて | 食べて | して | 来て |
| Potential | 書ける | 食べられる | できる | 来られる |
| Passive | 書かれる | 食べられる | される | 来られる |
| Causative | 書かせる | 食べさせる | させる | 来させる |
| Volitional | 書こう | 食べよう | しよう | 来よう |
| Imperative | 書け | 食べろ | しろ | 来い |
How to Tell Godan from Ichidan
Only ichidan verbs end in -eru or -iru that follow certain stem patterns. A rough decision tree:
- Does the verb end in -ru preceded by -e- or -i-? It might be ichidan.
- Otherwise it's godan. -u, -ku, -gu, -su, -tsu, -nu, -bu, -mu endings are always godan.
- Common ichidan-looking godan exceptions must be memorized: 帰る, 走る, 入る, 切る, 知る, 要る.
When in doubt, check a dictionary or learn the te-form - it disambiguates.
The Te-Form: The Key to Japanese Grammar
The te-form is used for:
- Connecting verbs in sequence: 食べて寝る (eat and then sleep).
- Making requests: 食べてください (please eat).
- Progressive aspect with いる: 食べている (is eating).
- Permission: 食べてもいい (may eat).
- Prohibition: 食べてはいけない (must not eat).
- Conditional nuances and many grammatical constructions.
Mastering the te-form rules for each verb class is essential.
Negative and Past Negative Stems
Table 8. Stem patterns for negative and past negative.
| Class | Negative stem | Past negative |
|---|---|---|
| Godan | -a + nai (替える stem: kak-a-nai) | -a + nakatta |
| Ichidan | stem + nai (tabe-nai) | stem + nakatta |
| する | shinai | shinakatta |
| 来る | konai | konakatta |
For godan, the -a- vowel appears because -u verbs shift to -a- stem for negation. 書く → 書か (kaka-), 飲む → 飲ま (noma-).
Common Mistakes Learners Make
- Mistaking ichidan-looking godan verbs. 帰る is godan - past tense is 帰った, not *帰た.
- Forgetting te-form rules for godan. Pronouncing 書いた as *書きた is wrong.
- Using ra-nuki kotoba in formal speech. 食べれる (can eat) is informal; 食べられる is standard.
- Confusing potential and passive of ichidan verbs. 食べられる can mean "can eat" or "be eaten"; context disambiguates.
- Conjugating 来る as if regular. 来ない (konai), 来ます (kimasu), 来る (kuru) - different vowels each time.
- Overusing する. Not every action noun + する is natural; some need 勉強する (study) patterns, not all noun combinations work.
- Dropping politeness marker inappropriately. In formal settings, always use masu-form unless addressed as casual speech.
- Mixing conditional forms. ば-conditional is hypothetical; たら is past-type conditional; と is natural-consequence.
Quick Reference
- Godan verbs: -u endings. Negative drops -u and adds -anai. Past follows te-form table.
- Ichidan verbs: -eru or -iru (specific stems). Drop る, add ending.
- Irregular: する and 来る. Memorize individually.
- Te-form is the single most important form to master.
- Potential = -れる/-られる/できる/来られる.
- Politeness is orthogonal: masu-form applies to any verb in polite contexts.
FAQ
How do I tell if a verb is godan or ichidan?
If it ends in -eru or -iru with specific stems, check a dictionary - it might be either. Otherwise (-u, -ku, -gu, -su, -tsu, -nu, -bu, -mu), it's godan.
What's the difference between ます-form and dictionary form?
Dictionary form is plain; ます-form is polite. In casual speech among friends, use plain. In formal speech or with strangers, use ます.
Can I use dictionary form in questions?
Yes in plain-form conversation among equals/friends. The ます-form in formal Japanese adds か for questions: 食べますか？
What is ra-nuki kotoba?
A colloquial Japanese trend to drop the ら in potential forms of ichidan verbs: 食べれる for 食べられる. Common in casual speech but considered nonstandard in writing.
Do Japanese verbs change for person?
No. One form - 食べる - covers "I eat," "you eat," "he eats," "we eat," "they eat." Subject is understood from context or marked with は/が.
How do I form a command?
Plain imperative: -e for godan (書け), -ro for ichidan (食べろ). Rarely used; harsh. Polite request: te-form + ください: 書いてください.
What are compound verbs?
Many Japanese verbs combine: 食べ始める (tabehajimeru, "begin to eat"), 書き終わる (kakiowaru, "finish writing"). The first verb uses its masu-stem; the second carries the conjugation.
See Also
- Japanese verb conjugation beginners guide
- Japanese particles wa ga o ni de to reference
- Japanese grammar particles complete guide
- Hiragana complete guide chart and stroke order
- Katakana complete guide
- Japanese counting numbers counters guide
- Japanese counters classifiers reference
- Japanese keigo honorific language reference
Frequently Asked Questions
How do I tell if a verb is godan or ichidan?
Ichidan verbs end in -eru or -iru with specific stem patterns; check a dictionary if uncertain. Everything else (-u, -ku, -gu, -su, -tsu, -nu, -bu, -mu) is godan.
What's the difference between ます-form and dictionary form?
Dictionary form is plain; ます-form is polite. Use plain with close friends/family; use ます in formal or unfamiliar contexts.
Can I use dictionary form in questions?
Yes in plain-form speech among equals. In polite speech, add か to the ます-form: 食べますか?
What is ra-nuki kotoba?
A colloquial trend to drop the ら in potential forms: 食べれる instead of 食べられる. Common in casual speech but considered nonstandard in writing.
Do Japanese verbs change for person?
No. One form covers all persons. Subject is understood from context or marked by は/が.
How do I form a command?
Plain imperative: godan take -e ending (書け), ichidan take -ro (食べろ). Harsh. Polite request uses te-form + ください: 書いてください.
What are compound verbs?
Pairings like 食べ始める (begin to eat) or 書き終わる (finish writing). The first verb's masu-stem attaches to a second verb that carries the inflection.
