Japanese Verb Conjugation: Complete Beginner's Guide

What Is Japanese Verb Conjugation?

Conjugation means changing a verb's form to express tense, politeness, negation, and more. In Japanese, conjugation follows highly regular patterns — once you understand the rules, you can apply them to any new verb you encounter. The good news: unlike English, Japanese verbs do not change based on the subject. 食べる (taberu, to eat) works whether the subject is I, she, or they. What does change, systematically, is the verb's ending.

The single most important concept to grasp before any conjugation rule makes sense is verb groups. Every Japanese verb belongs to one of three groups, and each group follows its own set of rules. Get the group right and the conjugation almost works itself out.

If you're still building the foundation for how verbs slot into sentences, the Japanese basic sentence structure guide is worth reading before continuing here. Japanese adjectives also conjugate — explore those patterns in the Japanese adjectives guide once verb forms feel solid.

The Three Verb Groups

Group 1: Godan Verbs (U-Verbs)

Godan verbs are the largest group. In their dictionary form, the final syllable falls on the う-row: ending in う, く, ぐ, す, つ, む, ぬ, ぶ, or る (with exceptions — see below).

To conjugate a godan verb, you shift the final syllable to a different vowel row depending on the form you need: - Negative: shift to the あ-row, then add ない - Polite: shift to the い-row, then add ます - て/past forms: vary by final sound — see the reference table below

Common examples: 飲む (nomu, drink), 書く (kaku, write), 話す (hanasu, speak), 帰る (kaeru, return home)

Group 2: Ichidan Verbs (Ru-Verbs)

Ichidan verbs always end in る, and the syllable immediately before る carries an i or e vowel. Conjugating them follows one rule: drop る, then add the appropriate ending.

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

Group 3: Irregular Verbs — する and くる

Only two truly irregular verbs exist in Japanese: する (suru, to do) and くる (kuru, to come). Their stems shift unpredictably. Because there are only two, you simply memorize them.

How to tell Group 1 from Group 2: If a verb does not end in る → it is always Group 1. If it ends in る and the vowel before る is i or e → almost certainly Group 2. If the vowel before る is a, u, or o → Group 1. A small number of exceptions exist: 帰る (kaeru), 切る (kiru, to cut), and 走る (hashiru, to run) all look like Group 2 but are Group 1. These are common verbs worth memorizing individually.

The Five Essential Conjugation Forms

Dictionary Form

The base form found in any dictionary — and the form all rules derive from.

Past Tense

• Ichidan: drop る → add た (ta). 食べる → 食べた (tabeta, ate)
• Godan む/ぬ/ぶ: → んだ (nda). 飲む → 飲んだ (nonda, drank)
• Godan く: → いた (ita). 書く → 書いた (kaita, wrote) — Exception: 行く → 行った (itta)
• Godan す: → した (shita). 話す → 話した (hanashita, spoke)
• Godan つ/う/る(G1): → った (tta). 帰る → 帰った (kaetta, returned)
• Irregular: した (shita) for する; きた (kita) for くる

Negative Form (Plain)

• Ichidan: drop る → add ない (nai). 食べる → 食べない (tabenai, don't eat)
• Godan: shift final syllable to あ-row → add ない. 飲む → 飲まない (nomanai, don't drink); 書く → 書かない (kakanai, don't write)
• Note: Verbs ending in う shift to わ. 買う (kau) → 買わない (kawanai, don't buy)
• Irregular: しない (shinai) for する; こない (konai) for くる

Polite Form (Masu-Form)

• Ichidan: drop る → add ます (masu). 食べる → 食べます (tabemasu)
• Godan: shift final syllable to い-row → add ます. 飲む → 飲みます (nomimasu); 書く → 書きます (kakimasu)
• Irregular: します (shimasu) for する; きます (kimasu) for くる

Cultural note: In Japanese, choosing between plain and polite speech is a social skill as much as a grammatical one. Using the masu-form with people you've just met — a teacher, a shopkeeper, a new colleague — is the baseline expectation in most public interactions, not a special formality. The guide to present-tense masu-form sentences covers this usage in everyday context.

て-Form (Te-Form)

The て-form links two actions ("eat and drink"), builds polite requests (〜てください), and forms progressive tenses.

• Ichidan: drop る → add て (te). 食べる → 食べて (tabete)
• Godan む/ぬ/ぶ: → んで (nde). 飲む → 飲んで (nonde)
• Godan く: → いて (ite). 書く → 書いて (kaite) — Exception: 行く → 行って (itte)
• Godan ぐ: → いで (ide). 泳ぐ (oyogu) → 泳いで (oyoide)
• Godan す: → して (shite). 話す → 話して (hanashite)
• Godan つ/う/る(G1): → って (tte). 帰る → 帰って (kaette)
• Irregular: して (shite) for する; きて (kite) for くる

Complete Conjugation Reference Table

All five forms across all three groups — Japanese script, Hepburn romaji, and English meaning in every cell.

Conjugation in Context

Seeing forms in real sentences locks in the rules far faster than drills alone.

1. 毎日、水を飲みます。 Mainichi, mizu o nomimasu. I drink water every day. (godan, polite form)

2. 昨日、すしを食べた。 Kinō, sushi o tabeta. I ate sushi yesterday. (ichidan, past plain)

3. 今日は学校に行かない。 Kyō wa gakkō ni ikanai. I'm not going to school today. (godan, negative plain — 行く: く → か + ない)

4. 友達が来て、一緒に勉強した。 Tomodachi ga kite, issho ni benkyō shita. My friend came and we studied together. (irregular くる て-form + irregular する past)

5. この本を読んでください。 Kono hon o yonde kudasai. Please read this book. (godan, て-form — 読む: む → んで)

Common Mistakes

Misidentifying る-ending verbs. Learners often assume every verb ending in る is ichidan. Common godan exceptions — 帰る (kaeru, return), 切る (kiru, cut), 走る (hashiru, run), 知る (shiru, know) — look like ichidan but follow godan rules completely. A reliable shortcut: if the vowel before る is a, u, or o, default to godan and verify. Memorize the most frequent exceptions explicitly.

Applying ichidan rules to godan verbs. A typical error is writing ✗ 飲ない instead of ✓ 飲まない (nomanai). The ichidan pattern — drop る, add ない — only works for ichidan verbs. Godan verbs always need the vowel-row shift first.

Over-applying one て-form pattern. Learners who learn 飲んで first tend to use む → んで for all godan verbs. 書いて, 行って, and 話して each follow a different pattern. Writing the full て-form chart from memory once — on paper, without looking — is one of the most effective ways to fix this.

Not applying する to compound verbs. Words like 勉強する (benkyō suru, to study) and 運動する (undō suru, to exercise) are simply nouns + する. They conjugate exactly like する: 勉強した (benkyō shita, studied), 勉強しない (benkyō shinai, don't study), 勉強して (benkyō shite, study and…). Recognizing this pattern instantly unlocks hundreds of vocabulary items without learning new rules.

Mixing plain and polite forms mid-conversation. Choosing the wrong register — especially slipping into plain form when speaking with someone you've just met — is a common social stumble for learners. Understanding the boundary between casual and formal contexts is as important as the conjugation itself, and it's covered in depth in the casual vs polite speech guide.

Still unsure which group a verb belongs to? A one-on-one teacher can pinpoint exactly where your pattern recognition breaks down and give you targeted drills in real time. Start a Free Trial lesson over LINE and practice Japanese verb conjugation with a native teacher — no preparation needed.

Practice Quiz

Test yourself before checking the answers.

Part 1 — Conjugate the Verb

Part 2 — What Does It Mean?

Part 3 — Fill in the Form

Answers

FAQ

How do I tell which verb group a Japanese verb belongs to?

If a verb doesn't end in る, it's always Group 1 (godan). If it ends in る and the vowel before it is i or e — like 食べる or 見る — it's almost certainly Group 2 (ichidan). If the vowel is a, u, or o, it's Group 1. Memorize the most common る-ending godan exceptions: 帰る, 切る, 走る, 知る.

Why do godan negatives shift to the a-row?

The negative suffix ない attaches to the verb's a-stem (未然形, mizenkei). Every godan verb has a stem that shifts across all five vowel rows: a-row for negative, i-row for polite, e-row for imperative, and so on. This vowel-row system is the underlying logic behind all godan conjugation — once you see it, the patterns stop feeling arbitrary.

What is the て-form actually used for?

The て-form is one of the most versatile forms in Japanese. It connects sequential actions (食べて飲んだ, tabete nonda — ate and drank), forms polite requests with ください (〜てください, please do…), and builds progressive tenses with いる (〜ている, is/am doing). Mastering its patterns early gives you access to a large range of grammar immediately.

Do I need to memorize all five forms at once?

No — and trying to can slow you down. Most learners start with the polite (masu) form and the plain negative, then add the て-form once those feel stable. The key is always to learn the rule, not just the output. With the rule in hand, every new verb becomes conjugatable the moment you encounter it.

Continue Learning

This lesson builds directly on what you covered in the guide to casual and polite speech forms — that context tells you which form to choose; this lesson tells you how to build it. Next, put your conjugated verbs to work in making comparisons in Japanese, where verb forms combine with comparison structures to express more nuanced ideas.

This article is Lesson 62 of the Kind Japanese 100-day beginner curriculum.