Grammar
Understand the rule and the nuance
Ask why one form fits, how it is built, what it means in context, and how it differs from a tempting alternative.
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AI-assisted Japanese study help
JLPT AI tutor: meet Keiko
Ask about grammar, vocabulary, reading passages, or a question you missed. Keiko uses the practice context you provide to explain the answer and suggest a useful next step.
Public examples need no account. A free account is required to send live messages.
Keiko
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Why does this sentence use に?
に marks the target here. Let's compare it with で using the full sentence.
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See how Keiko explains JLPT questions
These reviewed examples show the intended answer style. Open the matching live explanation to continue with the exact question context.
N4 grammar explanation
Why is 飲みながら correct?
毎朝、コーヒーを（ ）ながら、新聞を読みます。
Why did I get this wrong?
Answer: 2. 飲み
The pattern is the ます-stem + ながら: 飲みます becomes 飲み, then 飲みながら. It means “while drinking.” Both actions normally have the same subject, so the speaker drinks coffee while reading the newspaper.
Takeaway: Memory tip: remove ます, then add ながら.
The questions and preview explanations above are original examples written for this site, not official JLPT questions.
Practical uses
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Reading
Find the evidence in the passage
Keiko can quote the clue, trace contrast words such as ただし, and compare the answer with distractors.
Open an N3 reading example →Mistake review
Turn an error into a reusable rule
Ask directly from a completed practice question so Keiko receives the selected answer, correct answer, choices, level, and available context.
Take a short diagnostic first →Good uses
What Keiko can do
- Explain JLPT grammar and vocabulary with examples and contrasts.
- Point to evidence in a reading passage and unpack tempting distractors.
- Review a practice mistake with the question, options, and selected answer in context.
- Suggest next study steps using available practice history and weak areas.
- Respond in the learner's selected supported language.
Important limits
What Keiko cannot do
- Issue an official JLPT score, certificate, or guaranteed pass prediction.
- Replace the official JLPT organization, a qualified teacher, or professional advice.
- Reliably explain material that the learner has not supplied and Keiko cannot see.
- Promise perfect accuracy. AI explanations can be incomplete or incorrect.
- Verify changing registration rules unless the current official source is checked.
Contextual review
From a missed answer to a focused explanation
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Complete a practice question
Use a skill sample, timed section, mini mock, or another supported question flow.
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Choose Ask Keiko
The level, question, choices, selected answer, correct answer, and available passage or transcript are attached.
- 3
Ask a follow-up
Request a simpler explanation, another example, a contrast with a distractor, or a next practice step.
Allowance and pricing
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A free account is enough to try live tutoring. Paid plans are optional and are intended for learners who want unrestricted daily use and the extra coaching tools.
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- ✓ Resets at midnight UTC
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- ✓ Saved conversations
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- ✓ Generated weak-area practice tests
- ✓ Custom study plans
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- ✓ Every monthly feature
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Account and privacy
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Why live chat needs an account
Authentication protects conversations, applies the daily allowance to the correct learner, and lets Keiko connect explanations with available practice history.
What may be sent for an explanation
Your prompt and relevant question context may be sent to AI service providers. Prompts and responses are stored with the account. Do not enter sensitive personal information.
JLPT AI tutor questions
Is Keiko free to use?
Yes. A free account includes 10 Keiko messages per day, resetting at midnight UTC. Keiko Pro removes the daily message limit and adds longer responses, learning memory, generated practice tests, and custom study plans.
Do I need an account to use the JLPT AI tutor?
The public examples on this page require no account. A free account is required to send a live message so conversations can be protected, counted against the daily allowance, and saved to the correct learner.
Can Keiko explain a question I answered incorrectly?
Yes. On supported practice questions, Ask Keiko sends the question, answer choices, correct answer, selected answer, level, skill, and available passage or transcript as context for the explanation.
Are Keiko's answers always correct?
No. Keiko is AI-assisted and can be incomplete or wrong. Verify important grammar points, official exam rules, registration details, and high-stakes decisions with authoritative sources.
What happens to information I type into Keiko?
Prompts and AI responses are stored with the learner's account and may be sent with relevant question context to AI service providers to generate an answer. Do not include sensitive personal information. See the privacy policy for details.
Bring Keiko your next difficult question
Start with a free explanation, ask a follow-up in your selected language, and return to focused practice while the rule is still fresh.
Reviewed . Pricing and allowances should be checked whenever the product changes.