Common Japanese Mistake: Potential Form Errors (できる vs 〜られる vs 〜える)

Three Ways to Say “Can” in Japanese

English uses just one word for ability: “can.” Japanese has three main systems, and choosing wrong — or forming them incorrectly — is a very common intermediate-level mistake.

System 1: できる (For Nouns and する Verbs)

For abilities expressed as a noun + できる:

• にほんごができます。— I can [speak] Japanese.
• りょうりができます。— I can cook.
• うんてんができます。— I can drive.

Also: する verbs → にほんごをはなすことができます (can speak Japanese — using こと + できる).

System 2: Potential Form (〜える / 〜られる)

Common Mistake 1: Using を With Potential Form

When using the potential form, the direct object particle changes from を to が:

Note: を is not entirely wrong (many native speakers accept it in casual speech), but が is the standard textbook-correct particle with potential.

Common Mistake 2: ら-Dropping in Casual Speech

In very casual speech, Group 2 potential sometimes drops ら: たべれる (instead of たべられる). This is called ら抜き言葉 (ra-nuki kotoba). It’s common in conversation but considered non-standard in writing and formal speech.

Quick Drill: Make the Potential Form

1. かく (to write)
2. みる (to watch)
3. はなす (to speak)
4. くる (to come)

Answers: 1. かける / 2. みられる / 3. はなせる / 4. こられる

Yuka Can’t Figure Out the Potential Form

Mistakes feel embarrassing in the moment but they are the fastest way to learn. Watch how Yuka makes a natural error — and how Rei explains the rule clearly enough to prevent it from happening again.

Yuka

Rei, I wanted to say ‘I can eat sushi’ and wrote すしをたべることができます. My teacher said it was correct but long?

Rei

It IS correct — 〜ことができます is a valid potential expression. But the shorter natural form is the potential verb: すしがたべられます. Same meaning, much more fluid. Both are fine; the short form sounds more natural in conversation.

Yuka

How do I form the potential verb? I always get confused.

Rei

Group 1 (u-verbs): change the final う sound to える. 書く → 書ける. 飲む → 飲める. 話す → 話せる. Group 2 (ru-verbs): replace る with られる. 食べる → 食べられる. 見る → 見られる. Irregular: する → できる. くる → こられる.

Yuka

And why does the particle change from を to が with potential verbs?

Rei

With potential verbs, the object of ability is marked with が rather than を — すしがたべられる not すしをたべられる. However, を is increasingly accepted in casual speech. In formal writing and tests, use が. Either way, you’ll be understood perfectly.

5 Correct Sentences — Read These Aloud

Each sentence demonstrates the correct usage from this article. Say them aloud to lock in the right pattern.

1. かんじがよめますか？
   Can you read kanji?
2. にほんごがすこしはなせます。
   I can speak a little Japanese.
3. はやくはしれるようにれんしゅうしています。
   I’m practicing so I can run faster.
4. このフォームはスマホでもつかえます。
   This form can also be used on a smartphone.
5. むかしはからいものがたべられませんでしたが、いまはたべられます。
   I used to be unable to eat spicy food, but now I can.

Your Turn! Correct the Mistake in the Comments

Here is a sentence with the error from this article. Can you fix it? Write the corrected version — and your own correct sentence — in the comments below.

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