JLPT N4 6 min read Updated May 17, 2026 Grammar pattern

ではないか

isn’t it; don’t you think

Learn how to use ではないか, a JLPT N4 Japanese grammar point meaning isn’t it; don’t you think, with structure, nuance, examples, mistakes, and comparisons.

Meaning
isn’t it; don’t you think
Pattern
ではないか
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JLPT grammar
JLPT
N4

ではないか means isn’t it; don’t you think. It is a JLPT N4 Japanese grammar pattern used to seek confirmation or make an emphatic realization.

This grammar point often appears in conversation, written explanations, formal notices, and JLPT-style reading questions. If you want to seek confirmation or make an emphatic realization, ではないか is a useful pattern to learn after the N5 basics.

What does ではないか mean?

Use ではないか when you want to seek confirmation or make an emphatic realization.

Natural translations include:

  • isn’t it
  • right
  • isn’t it; right

The exact English translation changes with context. Focus on what the grammar point does in the sentence first, then choose the English phrase that sounds natural.

How to form ではないか

Plain statement + ではないか

Examples of the pattern:

  • 便利ではないか
  • いいではないか
  • 学生ではないか

Pay attention to the word form before the pattern. Many JLPT N4 mistakes happen because the meaning is understood, but the grammar is attached to the wrong form.

When is ではないか used?

Use ではないか in situations like:

  • explaining a condition, reason, decision, or time relationship
  • making a sentence more specific than a basic N5 pattern
  • understanding natural Japanese in conversation or reading

Tone and register:

  • neutral unless the grammar itself is marked as casual, humble, honorific, or formal
  • Common in daily speech, textbook examples, and JLPT N4 reading questions

ではないか example sentences

これは便利べんりではないか。
This is convenient, isn’t it?
na-adj
かれ学生がくせいではないか。
He is a student, isn’t he?
noun
いいかんがえではないか。
That is a good idea, isn’t it?
i-adj
もう時間じかんではないか。
It is already time, isn’t it?
noun
この方法ほうほうでできるではないか。
We can do it this way, can’t we?
verb

Read the Japanese sentence first, then check the English translation. Try to notice what the grammar point contributes: condition, timing, limitation, possibility, decision, politeness, or emphasis.

Nuance of ではないか

The key nuance is sounds less contracted and more formal.

This matters because ではないか may look simple in English, but the Japanese form tells you whether the speaker is describing a time, a condition, a decision, a possibility, or a social relationship.

For example:

  • In context, ではないか helps make the sentence more precise than a direct English translation.
  • Compared with じゃないか, it has a different focus even when both patterns appear in similar sentences.

ではないか vs じゃないか

Both ではないか and じゃないか can appear in related sentences, but they are different.

ではないか
Formal, less contracted
Use in formal speaking, writing, and polite contexts.
これは便利べんりではないか。
This is convenient, isn’t it?
vs
じゃないか
Casual, contracted
Use in casual conversation and informal contexts.
これは便利べんりじゃないか。
This is convenient, isn’t it?

If you are unsure which one to use, identify the main job of the sentence before translating it into English.

Common mistakes with ではないか

Attaching to the wrong form, like 便利だではないか.
Attach directly to the plain form: 便利ではないか.
Using じゃないか in formal writing where ではないか is expected.
Match register to context: ではないか for formal, じゃないか for casual.
Translating word-for-word without reading the full sentence context.
Read the whole sentence to confirm whether the speaker is seeking agreement or making a realization.

A good study habit is to write one short sentence and then change only the grammar point. This makes the difference between similar patterns easier to feel.

Is ではないか on the JLPT?

N4

Yes. ではないか is commonly taught as JLPT N4 grammar.

That means learners should be able to:

  • recognize it in reading
  • understand its nuance in context
  • use it in simple original sentences

For test preparation, do not only memorize the English gloss. Practice identifying the words around the grammar point, because JLPT questions often test structure and context together.

Practice questions for ではないか

1 Write one sentence using the basic pattern. production
2 Change the sentence into polite or casual style if possible. variation
3 Compare ではないか with じゃないか in your own example. comparison

Keep the sentences short at first. Once the form feels natural, add time words, places, reasons, or contrast to make the sentence more realistic.

Learning path for ではないか

1
Make sure you can form ではないか by attaching it to a plain statement without the copula .
2
Compare ではないか with じゃないか to feel the register difference.
3
Practice with different subjects, time expressions, and adjective types to build flexibility.
4
Review alongside related N4 patterns like のは〜だ and と思う to see how sentence boundaries and nuance shift.
  • のは〜だ — builds control over quoted thoughts, questions, names, and explanations.
  • と言ってもいい — builds control over quoted thoughts, questions, names, and explanations.
  • と思う — builds control over quoted thoughts, questions, names, and explanations.
  • という — builds control over quoted thoughts, questions, names, and explanations.

Learn ではないか with Hane

If you want to review ではないか together with the related patterns above, Hane helps you practice Japanese in short, focused sessions.

Browse more lessons here:

FAQ about ではないか

What does ではないか mean in Japanese?

ではないか means “isn’t it; don’t you think” in Japanese. It is an N4 grammar point, and this lesson explains its formation, nuance, example sentences, common mistakes, and similar grammar.

Is ではないか on the JLPT?

ではないか is taught as N4 Japanese grammar in Hane's grammar lesson archive. Review it with examples, usage notes, and related N4 patterns.

How should I practice ではないか?

Read several example sentences, identify the form before and after ではないか, then make your own short sentences and compare it with nearby grammar points.

Practice this with Hane
Drill ではないか until it’s automatic.

Short, focused iOS sessions for grammar, kanji, vocabulary, reading, and JLPT review. Use this lesson with the JLPT prep app and the Japanese learning app overview.

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