Ichidan Verbs (ru-verbs) in Japanese

In Brief

Ichidan verbs, often called ru-verbs or Group II verbs, follow a simple pattern: remove the final る from the dictionary form and add the ending you need. For example, 食べる → 食べます, 見ない, and 起きた. Most verbs ending in -いる or -える are ichidan, but common exceptions such as 入る and 帰る belong to another verb class.

Overview

Japanese verbs fall into conjugation classes: groups of verbs that change form in the same way. Ichidan literally means “one grade” or “one row.” The name reflects the fact that the part before る stays stable across the basic conjugations. In 食べる (“to eat”), for example, 食べ- remains visible in 食べます, 食べない, 食べた, and 食べて.

This is one of the first verb patterns learned at A1. It is useful immediately because many frequent verbs are ichidan: 見る (“to see; watch”), 起きる (“to get up”), 寝る (“to sleep; go to bed”), 開ける (“to open something”), and 教える (“to teach; tell”). Once you know the stem—the stable part left after removing る—you can build polite sentences, negatives, past forms, requests, and many later constructions.

English verbs often need an extra word to express meanings such as “did not eat” or “can eat.” Japanese commonly puts that information into a verb ending instead. Japanese verbs do not change for “I,” “you,” or “they”: 食べます can mean “I eat,” “you eat,” or “they eat,” depending on context. They do change for politeness and for forms such as positive, negative, past, and non-past.

How It Works

The beginner rule: remove る

Start with the dictionary form, the plain form used in dictionaries and casual affirmative statements. For an ichidan verb, remove final る to find the stem.

Dictionary form	Meaning	Stem	Polite non-past
食べる	to eat	食べ-	食べます
見る	to see; watch	見-	見ます
起きる	to wake up; get up	起き-	起きます
寝る	to sleep; go to bed	寝-	寝ます
開ける	to open something	開け-	開けます
教える	to teach; tell	教え-	教えます

A hyphen after a stem is only an explanatory device. Do not write it in Japanese.

The same stem accepts many endings:

Function	Pattern	食べる	見る
Polite non-past	stem + ます	食べます	見ます
Plain negative	stem + ない	食べない	見ない
Plain past	stem + た	食べた	見た
Plain negative past	stem + なかった	食べなかった	見なかった
て-form	stem + て	食べて	見て

“Non-past” means a form that can describe either present or future time. 食べます can therefore mean “eat,” “will eat,” or, in an appropriate context, “usually eat.” Time words and context make the intended time clear.

The polite ます forms

To speak politely, add ます to the stem. The ending ます itself changes for negative and past meanings.

Meaning	Ending	食べる	起きる
Polite non-past	ます	食べます	起きます
Polite non-past negative	ません	食べません	起きません
Polite past	ました	食べました	起きました
Polite past negative	ませんでした	食べませんでした	起きませんでした

These four forms are a practical A1 foundation. Notice that tense and negation are carried by the ending; the stem does not change.

Plain forms

Plain forms are used in casual conversation, dictionary entries, and grammar structures in which a verb comes before another element. “Plain” does not mean rude by itself, but using plain speech with the wrong person can sound overly familiar.

Meaning	Pattern	食べる	寝る
Non-past positive	dictionary form	食べる	寝る
Non-past negative	stem + ない	食べない	寝ない
Past positive	stem + た	食べた	寝た
Past negative	stem + なかった	食べなかった	寝なかった

English distinguishes “I eat” from “I will eat,” but Japanese normally uses the same non-past form for both. 今日は家で食べる can mean “I’m eating at home today” or “I’ll eat at home today,” depending on the situation.

The て-form

The て-form is a linking form: it connects a verb to requests, sequences, and many helper expressions. Ichidan formation is especially regular: remove る and add て.

• 食べる → 食べて
• 見る → 見て
• 起きる → 起きて
• 開ける → 開けて

Add ください for a polite request: 見てください (“Please look”) and ドアを開けてください (“Please open the door”). The て-form also appears in 食べています, which can mean “is eating” or, with some verbs, describe an ongoing state. That broader use belongs to a later grammar topic, but the ichidan stem rule remains the same.

How to recognize an ichidan verb

The most useful beginner test is:

1. The dictionary form ends in る.
2. The sound immediately before る is an i or e sound.
3. If both are true, the verb is probably ichidan.

Common shapes include -える in 食べる, 開ける, and 教える, and -いる in 見る, 起きる, and 借りる. This test is strong, not perfect. Japanese verb class is a property of each word, so it is best to learn a new verb together with its class or a revealing form such as its ます-form.

Verb	Meaning	Class	Revealing polite form
見る	to see; watch	ichidan	見ます
借りる	to borrow	ichidan	借ります
入る	to enter	godan	入ります
走る	to run	godan	走ります
帰る	to return	godan	帰ります
切る	to cut	godan	切ります

The godan verbs in the table keep an り before ます. An ichidan verb loses る completely: 見る → 見ます. This contrast is more dependable than guessing from English transliteration alone.

Also note that not every verb ending in る is a candidate for the -iru/-eru pattern. Verbs such as 取る (“take”) and 作る (“make”) are godan. する and 来る（くる） are irregular verbs and follow their own patterns.

Examples in Context

The omitted subject in these sentences is normal Japanese. A translation may include “I,” “we,” or “you” because English generally requires a subject where Japanese relies on context.

Japanese	English	Note
朝ごはんを食べます。	I eat breakfast.	Polite non-past; を marks what is eaten.
映画を見ます。	I watch movies.	見る → 見ます.
毎朝六時に起きます。	I get up at six every morning.	に marks the time.
ドアを開けます。	I open the door.	開ける is transitive: someone opens something.
今日は肉を食べません。	I won’t eat meat today.	Polite negative; context gives future meaning.
昨日はテレビを見ませんでした。	I didn’t watch TV yesterday.	Polite negative past.
十一時に寝ました。	I went to bed at eleven.	Polite past.
この本を借りてもいいですか。	May I borrow this book?	借りる → 借りて before もいいですか.
ここに名前を入れてください。	Please enter your name here.	入れる (“put in”) is ichidan; do not confuse it with 入る (“enter”).
窓を開けないでください。	Please do not open the window.	Stem + ないでください makes a polite negative request.
もう昼ごはんを食べた。	I already ate lunch.	Casual plain past.
その写真、見なかった。	I didn’t see that photo.	Casual plain negative past.
明日は早く起きる。	I’ll get up early tomorrow.	Plain non-past with future meaning.
先生が漢字を教えます。	The teacher teaches kanji.	が marks the person doing the action.

Common Mistakes

Treating every verb ending in る as ichidan

• Wrong: 帰る → 帰ます
• Right: 帰る → 帰ります
• Why: 帰る (“to return”) is godan even though it ends in an -eru sound. Learn frequent exceptions as complete pairs: 帰る・帰ります, 入る・入ります, 走る・走ります.

Leaving る before an ichidan ending

• Wrong: 食べるます
• Right: 食べます
• Why: For an ichidan verb, remove る before adding ます. Think 食べる → 食べ- → 食べます, not “add ます to the whole dictionary form.”

Using godan て-form rules on an ichidan verb

• Wrong: 食べってください
• Right: 食べてください。
• Why: Ichidan verbs take stem + て. The form with って belongs to certain godan verbs, such as 待つ → 待って and 帰る → 帰って.

Confusing 入る and 入れる

• Wrong: 名前がフォームに入ります when telling someone to enter a name
• Right: 名前をフォームに入れます。
• Why: 入る is the godan verb “to enter; go in,” while 入れる is the ichidan verb “to put in; insert.” Their particles and viewpoint differ: something が入る, but someone puts something を入れる.

Mixing polite and plain endings

• Wrong: 昨日、食べましたか。はい、食べたです。
• Right: 昨日、食べましたか。はい、食べました。
• Why: 食べた is already a plain past verb. Do not attach です to make it polite. In a polite exchange, use 食べました.

Assuming Japanese marks the subject on the verb

• Wrong idea: 食べます specifically means “I eat.”
• Right idea: 食べます is polite and can have many subjects.
• Why: Unlike English “eat/eats,” an ichidan verb has no separate person ending. Context or an explicit phrase such as 田中さんが identifies who acts.

Usage Notes

“Ru-verb” is a useful label, not a spelling rule

Learner materials often call ichidan verbs “ru-verbs” because their dictionary forms end in る. The label is convenient, but it can mislead: many godan verbs also end in る. “Group II” and “ichidan” refer to the conjugation class, not merely the final character.

Plain and polite speech use the same verb class

Ichidan does not mean casual or polite. 食べる is plain, while 食べます is polite; both are forms of the same verb. Choose the speech style according to the relationship and setting. Polite ます forms are a safe starting point with strangers, staff, teachers, and new acquaintances. Plain forms are common with close friends and family and inside many larger grammatical patterns.

Subjects and objects are often omitted

Japanese omits information that is already understood. もう食べましたか literally leaves both the eater and the food unstated, but naturally means “Have you eaten already?” in the right context. Do not force an English-style subject into every sentence. At the same time, particles remain important when a noun is stated: パンを食べます marks bread as the direct object—the thing directly affected by eating.

Learn related verbs carefully

Pairs can differ in both meaning and verb class. 開く（あく） is a godan verb meaning that something opens, while 開ける（あける） is an ichidan verb meaning that someone opens something:

• ドアが開きます。 — “The door opens.”
• ドアを開けます。 — “I open the door.”

Learning the particle with the verb helps prevent mistakes more effectively than memorizing an English gloss alone.

Beyond the Basics / Advanced Use

You do not need to master all of these forms at A1, but the same stable stem will make later grammar easier. Several useful ichidan forms are built directly from it.

Function	Basic pattern	食べる	Approximate meaning
Volitional	stem + よう	食べよう	let’s eat; I’ll eat
Conditional	stem + れば	食べれば	if [someone] eats
Potential	stem + られる	食べられる	can eat
Passive	stem + られる	食べられる	is eaten
Causative	stem + させる	食べさせる	make/let [someone] eat
Imperative	stem + ろ	食べろ	eat!

The potential and passive of an ichidan verb have the same visible form. Context and particles identify the meaning: 私は魚が食べられる usually means “I can eat fish,” while 魚が猫に食べられた means “The fish was eaten by a cat.”

In casual speech, you may hear a shortened potential without ら, such as 食べれる or 見れる. This is called ら抜き言葉 (“ra-omitted language”). It is widespread in conversation, but standard teaching and careful writing generally prefer 食べられる and 見られる. Beginners should learn the full standard forms first.

Some ichidan verbs are written with a final る that is part of the reading but not the kanji, such as 見る and 寝る. Others have longer stems, such as 食べる and 教える. The number of written kana does not alter the conjugation rule. Even the one-syllable stem 見- takes endings regularly: 見ない, 見た, 見て, 見よう.

A small number of formal or literary patterns use forms that beginners rarely need. For example, the negative ending ぬ can attach to an ichidan stem as 食べぬ. In modern everyday speech, 食べない is the normal choice. Recognizing such forms later is useful, but producing them is not part of the beginner rule.

Practice Tips

1. Learn a three-form set. For each new verb, record the dictionary form, polite form, and て-form: 起きる・起きます・起きて. An exception becomes obvious when the middle form keeps り, as in 帰る・帰ります・帰って.
2. Build a four-corner drill. Take one ichidan verb and say polite positive, polite negative, polite past, and polite negative past: 見ます・見ません・見ました・見ませんでした. Then repeat with its four plain forms.
3. Practice with particles and real routines. Write five true sentences about your day, such as 七時に起きます, 朝ごはんを食べます, and 十一時に寝ます. This teaches the conjugation together with time に and object を, rather than as an isolated chart.

Related Concepts

• Prerequisite: Basic Particles は/が/を/に — helps you show the topic, subject, object, and time used with these verbs.