THE potential form in Japanese indicates that someone can perform an action or that an action is possible under current conditions. For example, 話せます means “I can speak,” while 使えません can mean “it is not possible to use.”.
This form is not, by itself, formal or informal. Politeness depends on the ending: 話せる belongs to the plain style and 話せます to the polite style. The construction verb + ことができる expresses similar meanings and can also appear in both registers.
What does the potential form express?
The potential form, called 可能形 (kanōkei), presents an action as possible. The context shows whether the sentence talks about a person's ability, an opportunity, or an external condition.
私は日本語が話せます。
わたしは にほんごが はなせます。
Watashi wa nihongo ga hanasemasu.
I can speak Japanese.
この美術館では写真が撮れません。
この びじゅつかんでは しゃしんが とれません。
Kono bijutsukan de wa shashin ga toremasen.
It is not possible to take photos in this museum.
The first sentence describes an ability. The second presents an impossibility caused by the rules or conditions of the place. In Portuguese, the two ideas are often translated with “poder” or “conseguir.”.
Are the potential form and ことができる equivalent?
The two constructions can express ability and possibility. There is no rule according to which ことができる is necessarily informal and the potential form is formal. Compare:
| Structure | Plain style | Polite style |
|---|---|---|
| Potential form | 日本語が話せる | 日本語が話せます |
| ことができる | 日本語を話すことができる | 日本語を話すことができます |
The potential form tends to be more compact. ことができる makes the action explicit as a unit — literally, “it is possible to do the act of…”. Therefore, it appears frequently in explanations about services, rules, resources, and available activities. The choice depends on the sentence and context, not on a fixed formality opposition.
How to form verbs in the potential form
First, identify whether the verb is godan, ichidan, or irregular. If this division is not yet clear, review the Verb groups in Japanese.
Godan verbs: change from the U column to the E column and add る
In godan verbs, the last mora changes to the corresponding one in the E column and receives る.
| Ending | Change | Example | Potential form |
|---|---|---|---|
| う | える | 買う (kau) | 買える (kaeru) |
| く | ける | 書く (kaku) | 書ける (kakeru) |
| ぐ | げる | 泳ぐ (oyogu) | 泳げる (oyogeru) |
| す | せる | 話す (hanasu) | 話せる (hanaseru) |
| つ | てる | 待つ (matsu) | 待てる (materu) |
| ぬ | ねる | 死ぬ (shinu) | 死ねる (shineru) |
| ぶ | べる | 遊ぶ (asobu) | 遊べる (asoberu) |
| む | める | 読む (yomu) | 読める (yomeru) |
| る | れる | 帰る (kaeru) | 帰れる (kaereru) |
The verb 帰る ends in る, but it's godan. Therefore, the form 帰れる, and not 帰られる. The visual ending alone is not enough to determine the group.
Ichidan verbs: remove る and add られる
- 食べる → 食べられる (taberu → taberareru) — to be able to eat;
- 見る → 見られる (miru → mirareru) — to be able to see;
- 起きる → 起きられる (okiru → okirareru) — to be able to wake up or get up.
Irregular verbs
- する → できる (suru → dekiru) — to be able to do;
- 来る → 来られる (kuru → korareru) — to be able to come.
Compounds in する follow the same pattern: 予約する will come 予約できる and 勉強する will come 勉強できる.
How to conjugate a potential verb
Once formed, most potential forms behave like an ichidan verb. Thus, it is possible to create negative, past, and polite forms with a regular pattern. The pages about plain form of verbs and the ます form help you review these endings.
| Function | 話せる | 食べられる |
|---|---|---|
| Non-past affirmative | 話せる | 食べられる |
| Non-past negative | 話せない | 食べられない |
| Affirmative past | 話せた | 食べられた |
| negative past | 話せなかった | 食べられなかった |
| Polite affirmative | 話せます | 食べられます |
| Polite negative | 話せません | 食べられません |
Personal ability and situational possibility
Ability or skill
妹は百メートル泳げます。
いもうとは ひゃくメートル およげます。
Imōto wa hyaku mētoru oyogemasu.
My sister can swim a hundred meters.
The sentence describes a person's ability. The same reasoning appears in 漢字が読める (“can read kanji”) and 車を運転できる (“know how to/can drive”).
Condition, opportunity, or practical permission
この図書館では無料でWi-Fiが使えます。
この としょかんでは むりょうで ワイファイが つかえます。
Kono toshokan de wa muryō de waifai ga tsukaemasu.
In this library, you can use Wi-Fi for free.
The person may or may not have a special skill; the main point is that the place offers that possibility. That's why signs, guides, and service descriptions use the potential form so much, as well as ことができます.
Should I use the particle が or を?
In the transformation taught to beginners, the object marked by を usually appears with が before the potential form:
日本語を話します。 — I speak Japanese.
日本語が話せます。 — I can speak Japanese.
This is a neutral and safe pattern. However, sentences with を also occur in contemporary speech and writing, especially when the speaker keeps the action and its object in focus. Therefore, 私はパンを食べられる should not be automatically dismissed as wrong.
To begin with, use が in neutral statements of ability and learn to recognize を in real usage. The guide on basic particles in japanese helps review the general function of these markers in the sentence.
How to distinguish potential and passive voice
In ichidan verbs and in 来る, the form in られる can also have a passive meaning. The context and particles show the interpretation.
私は魚が食べられます。
Watashi wa sakana ga taberaremasu.
I can eat fish. (potential)
魚は猫に食べられました。
Sakana wa neko ni taberaremashita.
The fish was eaten by the cat. (passive)
In the first sentence, 私 is the one who has the ability. In the second, 魚 receives the action and 猫に indicates the agent. Translating the ending in isolation is not enough.
見れる e 食べれる: what is ら抜き?
In speech, you will also hear 見れる, 食べれる and 来れる, forms in which the ら in 見られる, 食べられる and 来られる was omitted. This phenomenon is called ら抜き言葉 (ranuki kotoba).
The usage is real and widespread, especially in spoken language, but acceptance varies by region, generation, and level of formality. To build a stable foundation and write in more careful situations, prefer the full forms first 見られる, 食べられる and 来られる. When you hear versions without ら, recognize them as usage variations, not as a new verb group.
Potential form, たい form, and ましょう
| Form | Main question | Example |
|---|---|---|
| Potential | Is it possible? Can the person do it? | 日本語が話せる — I can speak Japanese. |
| たい | Does the person want to do it? | 日本語を話したい — I want to speak Japanese. |
| ましょう | Shall we do it together? | 日本語を話しましょう — Let's speak Japanese. |
Ability, desire, and proposal are different intentions. To deepen the contrast, refer to the たい form of verbs and the ましょう form.
Common mistakes with the potential form
- Treating potential as a synonym for formality: 話せる is simple; 話せます is polite.
- Saying that ことができる is always informal: ことができます is a polite and perfectly normal construction.
- Classifying every verb ending in いる or える as ichidan: 帰る is godan and becomes 帰れる.
- Conjugating する regularly: the potential form is できる.
- Prohibiting を in any potential sentence: が is the neutral didactic standard, but を also appears in real usage.
- Ignoring the ambiguity of られる: in ichidan verbs, context separates potential and passive.
Mini dialogue with ability and possibility
A: 日本語が話せますか。
Nihongo ga hanasemasu ka.
Can you speak Japanese?
B: 少し話せます。でも、漢字はあまり読めません。
Sukoshi hanasemasu. Demo, kanji wa amari yomemasen.
I can speak a little. But I can't read many kanji.
A: このアプリで漢字を調べることができますよ。
Kono apuri de kanji o shiraberu koto ga dekimasu yo.
You can look up kanji with this app.
B: そうですか。これなら読めそうです。
Sō desu ka. Kore nara yomesō desu.
I see. With this, it seems I'll be able to read.
Potential form exercises
Convert each verb to the simple potential form. Then, complete the sentences.
- 書く → ______
- 食べる → ______
- 来る → ______
- する → ______
- 話す: I can speak a little Japanese ______.
- 見る: The sea is visible from here ______.
Show answers
- 書ける
- 食べられる
- 来られる
- できる
- 話せる
- 見られる
Summary and next steps
For godan verbs, change the final mora from the U column to the E column and add る. For ichidan, remove る and use られる. Also memorize する → できる and 来る → 来られる.
After formation, note three points: context separates ability from possibility; the simple or polite ending defines the register; and particles help interpret the function of participants. To connect this topic to the rest of the language, see the Basics of Japanese Grammar.
Frequently asked questions about the potential form
What is the potential form used for in Japanese?
The potential form expresses that someone is able to perform an action or that the action is possible in a given situation. The context distinguishes ability, opportunity, and external condition.
How to transform a verb into the potential form?
In godan verbs, change the ending from the U column to the E column and add る. In ichidan, remove る and use られる. The main irregulars are する → できる and 来る → 来られる.
What is the difference between the potential form and ことができる?
The two constructions can express ability and possibility. The potential form is more compact; ことができる makes the action explicit as a unit. Both can be plain or polite.
Should I use が or を with the potential form?
が is the neutral standard normally taught, as in 日本語が話せます. However, を also appears in contemporary speech and writing and should not be automatically considered incorrect.
Are 見れる and 食べれる correct?
These forms without ら are common in speech and represent the variation called ら抜き. For a safe foundation and for more careful situations, prefer 見られる, 食べられる, and 来られる first.
Official sources consulted
- Irodori, lesson 5 of Elementary 2 level — formation and uses of the potential form
- Irodori, lesson 5 of Elementary 1 level — construction verb + ことができます
- NINJAL — variation between が and を with potential verbs
- Agency for Cultural Affairs of Japan — history and variation of ら抜き言葉
- Marugoto — examples of affirmative and negative potential form