Japanese Conjugation: Complete U-Verbs & Ru-Verbs Guide

Understanding which group a verb belongs to is the first step to conjugating correctly. The group determines which conjugation pattern to follow.

U-Verbs (Five-Dash Godan)

U-verbs end in -u, -ku, -gu, -su, -tsu, -nu, -bu, -mu, or -ru. The key: the syllable before -ru is NOT an i or e sound. Also called Group 1 or consonant-stem verbs.

Examples: 書く (kaku, write), 話す (hanasu, speak), 飲む (nomu, drink), 買う (kau, buy).

Ru-Verbs (One-Dash Ichidan)

Ru-verbs end in -iru or -eru only. Also called Group 2 or vowel-stem verbs. These are simpler to conjugate than u-verbs.

Examples: 食べる (taberu, eat), 見る (miru, see), 起きる (okiru, wake up), 寝る (neru, sleep).

Irregular Verbs

Only two truly irregular verbs exist: する (suru, to do) and 来る (kuru, to come). These must be memorized separately. They conjugate as: する → します (shimasu), 来る → 来ます (kimasu).

Tricky Verbs to Watch

Some verbs LOOK like ru-verbs but are actually u-verbs. You must memorize these individually: 帰る (kaeru, return), 走る (hashiru, run), 入る (hairu, enter), 知る (shiru, know), 切る (kiru, cut).

The masu-form is the polite present/future tense used in most everyday conversations. You will use this form more than any other in real life.

Conjugating Ru-Verbs to Masu-Form

Drop the final -ru and add -masu. This is the simplest conjugation pattern.

• 食べる → 食べます (tabemasu, eat or will eat)
• 見る → 見ます (mimasu, see or will see)

Conjugating U-Verbs to Masu-Form

Change the final -u vowel to -i and add -masu. The change follows the kana chart vowel row:

• -ku → -kimasu (書く → 書きます kakimasu, write)
• -gu → -gimasu (泳ぐ → 泳ぎます oyogimasu, swim)
• -su → -shimasu (話す → 話します hanashimasu, speak)
• -tsu → -chimasu (待つ → 待ちます machimasu, wait)
• -nu → -nimasu (死ぬ → 死にます shinimasu, die)
• -bu → -bimasu (飲む → 飲みます nomimasu, drink)
• -mu → -mimasu (included above)
• -ru → -rimasu (帰る → 帰ります kaerimasu, return)
• -u → -imasu (買う → 買います kaimasu, buy)

Negative Masu-Form

Change -masu to -masen for the negative:

• 食べます → 食べません (tabemasen, don't eat)
• 書きます → 書きません (kakimasen, don't write)

Irregular Masu-Forms

The two irregular verbs are: する → します (shimasu, do), 来る → 来ます (kimasu, come).

The te-form is the most versatile conjugation in Japanese. Use it for making requests, expressing ongoing actions (with iru), connecting sentences, and many grammar patterns. This is arguably the single most important form to master first.

Ru-Verbs to Te-Form

Drop -ru and add -te. This is simple and consistent across all ru-verbs.

• 食べる → 食べて (tabete)
• 見る → 見て (mite)

U-Verbs to Te-Form

The pattern varies based on the final consonant sound. The rule mirrors the masu-form but uses -te/-de instead of -i + masu:

• -ku → -ite (書く → 書いて kaite, write). Exception: 行く → 行って (itte, go)
• -gu → -ide (泳ぐ → 泳いで oyoide, swim)
• -su → -shite (話す → 話して hanashite, speak)
• -tsu, -ru, -u → -tte (待つ → 待って matte, wait; 買う → 買って katte, buy; 帰る → 帰って kaette, return)
• -nu, -bu, -mu → -nde (死ぬ → 死んで shinde, die; 飲む → 飲んで nonde, drink; 遊ぶ → 遊んで asonde, play)

Irregular Te-Forms

The irregular verbs are: する → して (shite, do), 来る → 来て (kite, come).

Common Te-Form Uses

• てください (please do X)
• ている (is doing, state of being)
• てもいい (may I, is it okay to)
• てはいけない (must not, cannot)
• て connecting sentences together

The plain past tense (ta-form) follows exactly the same pattern as the te-form. Instead of -te/-de, use -ta/-da. If you know te-form, you automatically know the past tense.

Ru-Verbs to Ta-Form

Drop -ru and add -ta:

• 食べる → 食べた (tabeta, ate)
• 見る → 見た (mita, saw)

U-Verbs to Ta-Form

Follow the same pattern as te-form but with -ta/-da:

• 書く → 書いた (kaita, wrote)
• 飲む → 飲んだ (nonda, drank)
• 買う → 買った (katta, bought)
• 話す → 話した (hanashita, spoke)
• 待つ → 待った (matta, waited)

Polite Past (Mashita-Form)

Change -masu to -mashita:

• 食べます → 食べました (tabemashita, ate)
• 書きます → 書きました (kakimashita, wrote)

Negative Past Forms

For plain negative past, change -nai to -nakatta:

• 食べない → 食べなかった (tabenakatta, didn't eat)
• 書かない → 書かなかった (kakanakatta, didn't write)

For polite negative past, change -masen to -masen deshita:

• 食べません → 食べませんでした (tabemasen deshita, didn't eat)

Irregular Past Forms

The irregular verbs are: する → した (shita, did), 来る → 来た (kita, came).

The plain negative form always ends in -nai. Use it for casual speech, expressing inability, and building many grammar patterns.

Ru-Verbs to Negative Form

Drop -ru and add -nai:

• 食べる → 食べない (tabenai, don't eat)
• 見る → 見ない (minai, don't see)

U-Verbs to Negative Form

Change the final -u vowel to -a and add -nai:

• 書く → 書かない (kakanai, don't write)
• 話す → 話さない (hanasanai, don't speak)
• 飲む → 飲まない (nomanai, don't drink)

Special Case: Verbs Ending in -u

Verbs with a vowel stem (like 買う kau, buy) change to -wanai, NOT -awanai:

• 買う → 買わない (kawanai, don't buy)

Irregular Negative Forms

The irregular verbs are: する → しない (shinai, don't do), 来る → 来ない (konai, don't come).

The Special Verb Aru

The verb ある (aru, to exist for inanimate things) has a unique negative: ない (nai, doesn't exist). Do not use *あらない.