Japanese Verb Groups: Ru-Verbs, U-Verbs and Irregular Verbs
By the Kantan JLPT team · · 8 min read
Quick answer: Japanese verbs fall into three groups. U-verbs (group 1) end in an -u sound like かく or のむ. Ru-verbs (group 2) end in -iru or -eru, like みる or たべる. Irregular verbs (group 3) are just する and くる. The catch: some verbs that end in -iru or -eru, like かえる (go home) and はいる (enter), are actually u-verbs, so you have to learn those by heart.
Why verb groups matter
Every verb form you learn, from polite ます to te-form to potential, is built differently depending on the group. Get the group wrong and the conjugation comes out wrong. The good news is that Japanese verbs are very regular once you know the group: there are only two true irregular verbs.
Verb groups are the foundation for nearly everything in our Japanese grammar guide. Once you're comfortable with them, the next step is the Japanese te-form.
What are the names of the verb groups?
Textbooks use different names for the same three groups, which confuses many beginners:
| This article | Other names | Examples |
|---|---|---|
| U-verbs | Group 1, godan verbs, consonant-stem verbs | かく (write), のむ (drink), はなす (speak) |
| Ru-verbs | Group 2, ichidan verbs, vowel-stem verbs | たべる (eat), みる (see), ねる (sleep) |
| Irregular verbs | Group 3 | する (do), くる (come) |
How do you identify a ru-verb?
A ru-verb always ends in る, and the sound right before る is an -i or -e sound:
- みる (mi-ru), おきる (o-ki-ru), あびる (a-bi-ru)
- たべる (ta-be-ru), ねる (ne-ru), おしえる (o-shi-e-ru)
If a verb ends in -iru or -eru, it's probably a ru-verb. "Probably" is important, as you'll see below.
How do you identify a u-verb?
Any verb that doesn't end in -iru or -eru is a u-verb (except する and くる). That includes everything ending in う, く, ぐ, す, つ, ぬ, ぶ, む, and verbs ending in -aru, -oru or -uru:
- かう (buy), かく (write), およぐ (swim), はなす (speak), まつ (wait)
- しぬ (die), あそぶ (play), のむ (drink)
- ある (exist), とる (take), つくる (make), わかる (understand)
Which -iru and -eru verbs are u-verbs?
This is where learners trip up. These verbs look like ru-verbs but conjugate as u-verbs:
| Verb | Kanji | Meaning | Masu-form |
|---|---|---|---|
| かえる | 帰る | go home | かえります |
| はいる | 入る | enter | はいります |
| はしる | 走る | run | はしります |
| しる | 知る | know | しります |
| きる | 切る | cut | きります |
| いる | 要る | need | いります |
| しゃべる | 喋る | chat | しゃべります |
| へる | 減る | decrease | へります |
| すべる | 滑る | slip, slide | すべります |
| にぎる | 握る | grip | にぎります |
A few of these have a ru-verb twin that sounds the same, so the kanji helps:
- 着る (wear) is a ru-verb: きます. 切る (cut) is a u-verb: きります.
- いる (exist, for people and animals) is a ru-verb: います. 要る (need) is a u-verb: いります.
- 変える (change) is a ru-verb: かえます. 帰る (go home) is a u-verb: かえります.
There's no rule that predicts these. The practical approach is to learn each one as you meet it. At N5 and N4, かえる, はいる, はしる, しる and きる (cut) are the ones you'll see most.
What are the dictionary form and the masu-form?
The dictionary form is the plain, basic form you find in a dictionary: たべる, かく, する. It's used in casual speech and in many grammar patterns.
The masu-form is the polite form used with people you don't know well: たべます, かきます, します. Most N5 textbooks start here.
Here's how each group makes it:
- Ru-verbs: drop る, add ます. たべる → たべます, みる → みます
- U-verbs: change the final -u sound to its -i sound, add ます. かく → かきます, のむ → のみます, はなす → はなします, まつ → まちます, かう → かいます, かえる → かえります
- Irregular: する → します, くる → きます
まいにち コーヒーを のみます。
Mainichi kōhī o nomimasu. I drink coffee every day.
ろくじに うちに かえります。
Roku-ji ni uchi ni kaerimasu. I go home at six.
How does the nai-form work?
The nai-form is the plain negative ("don't do"). It also shows the groups clearly:
- Ru-verbs: drop る, add ない. たべる → たべない, みる → みない
- U-verbs: change the final -u sound to its -a sound, add ない. かく → かかない, のむ → のまない, はなす → はなさない, まつ → またない
- U-verbs ending in う: the う becomes わ, not あ. かう → かわない, あう → あわない
- ある: the negative is just ない, not あらない
- Irregular: する → しない, くる → こない
きょうは がっこうに いかない。
Kyō wa gakkō ni ikanai. I'm not going to school today.
The nai-form is also a handy test. If you're unsure whether a verb is a ru-verb or a u-verb, think of its negative: かえらない (u-verb) vs たべない (ru-verb).
Verb group conjugation table
| Dictionary | Group | Meaning | Masu | Nai | Te | Ta (past) |
|---|---|---|---|---|---|---|
| たべる | Ru | eat | たべます | たべない | たべて | たべた |
| みる | Ru | see | みます | みない | みて | みた |
| かう | U | buy | かいます | かわない | かって | かった |
| かく | U | write | かきます | かかない | かいて | かいた |
| およぐ | U | swim | およぎます | およがない | およいで | およいだ |
| はなす | U | speak | はなします | はなさない | はなして | はなした |
| まつ | U | wait | まちます | またない | まって | まった |
| しぬ | U | die | しにます | しなない | しんで | しんだ |
| あそぶ | U | play | あそびます | あそばない | あそんで | あそんだ |
| のむ | U | drink | のみます | のまない | のんで | のんだ |
| かえる | U | go home | かえります | かえらない | かえって | かえった |
| いく | U | go | いきます | いかない | いって | いった |
| する | Irregular | do | します | しない | して | した |
| くる | Irregular | come | きます | こない | きて | きた |
Common mistakes
- Conjugating 帰る as a ru-verb. ✗ かえます / かえない → ✓ かえります / かえらない
- Using あらない. ✗ あらない → ✓ ない
- Writing かあない for かう. ✗ かあない → ✓ かわない
- Reading くる's forms by the dictionary vowel. ✗ くない → ✓ こない, ✗ くます → ✓ きます
- Forgetting that する verbs are irregular. べんきょうする, そうじする and other noun + する verbs all follow する: べんきょうします, べんきょうしない.
Frequently asked questions
How many irregular verbs are there in Japanese?
Only two true ones: する and くる. A few verbs have one odd form, like いく (te-form いって) and ある (negative ない), but otherwise they follow the u-verb pattern.
Can you tell the group from the masu-form?
Not always. たべます and しります don't show whether the dictionary form is a ru-verb or a u-verb unless you already know it. That's why it's best to learn new verbs in their dictionary form, with the group noted.
Should I learn "ru-verb/u-verb" or "group 1/group 2"?
Whichever your main textbook uses. Being able to recognize all the names helps when you use several resources. The JLPT doesn't ask you to name groups; it tests whether you can use the right forms.
Are verb groups on the JLPT N5?
Indirectly, yes. Many N5 grammar questions depend on picking the correctly conjugated verb, and that depends on knowing its group.
Learn the group with the word
The simplest habit is to never learn a verb without its group. In Kantan JLPT, verb cards show the group alongside the meaning, and tricky ones like 帰る and 要る come back in review until you stop treating them as ru-verbs. Once groups feel solid, move on to particles like に vs で.