JLPT N1 6 min read Updated May 18, 2026 Grammar pattern

ではあるまいし

it’s not like; it isn’t as if ~

Learn how to use ではあるまいし, a JLPT N1 Japanese grammar point meaning it’s not like, with structure, nuance, examples, mistakes, and comparisons.

Meaning
it’s not like; it isn’t as if ~
Pattern
ではあるまいし
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JLPT grammar
JLPT
N1

ではあるまいし means it’s not like; it isn’t as if ~. It is a JLPT N1 Japanese grammar pattern used to dismiss an unrealistic or exaggerated assumption and then state a natural conclusion or expectation.

This grammar point often appears in conversation, light essays, and JLPT N1 reading passages. If you want to push back against an assumption—saying “come on, it’s not like you’re a child” or “it isn’t as if this is your first time”—ではあるまいし is a pattern that makes your Japanese sound sharper and more natural.

What does ではあるまいし mean?

Use ではあるまいし when you want to reject a hypothetical scenario to justify an action or expectation. It sets up a contrast: “(It’s) not like X, so Y should hold / Y is only natural.”

Natural translations include:

  • it’s not like; it isn’t as if ~
  • (you’re) not ~ so come on ~
  • there’s no way that ~, so obviously ~

The best translation depends on the sentence. Try to notice what assumption the speaker is knocking down, then choose an English phrase that carries the same dismissive-but-logical tone.

How to form ではあるまいし

Noun ではあるまいし
な-adj stem ではあるまいし

For verbs and い-adjectives, the pattern does not attach directly. Instead you rephrase with a noun-like clause:

Verb (dictionary form) ではあるまいし

Examples of the pattern:

  • 子供(こども)ではあるまいし
  • 簡単(かんたん)ではあるまいし
  • 初めて(はじめて)会う(あう)のではあるまいし

The form before the grammar point matters. In JLPT questions, the wrong answer choices often use a similar meaning but attach it to the wrong type of word.

When is ではあるまいし used?

Use ではあるまいし in situations like:

  • brushing off an excuse or over-cautious behaviour
  • pointing out that a situation is ordinary, so someone shouldn’t overthink it
  • adding a logical follow-up that would be obvious unless something extreme were true

Tone and register:

  • casual to conversational-assertive; common in spoken Japanese, advice-giving, and character dialogue
  • Common in JLPT N1 listening and reading comprehension

ではあるまいし example sentences

()(ども)ではあるまいし、自分(じぶん)片付(かたづ)けなさい。
You’re not a child, so clean up after yourself.
daily scolding
(はじ)めて()うのではあるまいし、そんなに緊張(きんちょう)しなくてもいいよ。
It’s not like it’s your first time meeting them— you don’t have to be that nervous.
friendly reassurance
簡単(かんたん)ではあるまいし、一晩(ひとばん)()わらせようなんて無理(むり)だ。
It’s not like this is easy—there’s no way you can finish it in one night.
realistic push-back
( )金持(かねも)ちではあるまいし、毎月(まいつき)そんな贅沢(ぜいたく)はできない。
We’re not rich—we can’t afford that kind of luxury every month.
household reality
神様(かみさま)ではあるまいし、(なに)もかも()っているわけがない。
He isn’t a god—there’s no way he knows everything.
everyday logic
昨日(きのう)(わたし)ではあるまいし、もうそんな(だま)()には()らない。
I’m not the person I was yesterday—I won’t fall for that trick anymore.
self-reassurance

After reading each sentence, ask what assumption is being denied. The speaker is saying “stop treating this like it’s X, therefore Y is the obvious consequence.” That logic makes the nuance easier to remember than a word-for-word translation.

Nuance of ではあるまいし

The key nuance is the speaker treats the preceding noun as an unrealistic premise and immediately rejects it to justify a logical conclusion.

This matters because a phrase like “子供(こども)ではあるまいし” does more than say “you are not a child.” It implies “if you were a child, your behaviour might be understandable, but you aren’t, so act accordingly.” The pattern packs a mild scolding, a reality check, or sometimes a comforting pat on the back.

In conversation, it often softens what could be a direct imperative or a blunt statement. By first denying an extreme scenario, you make the following point feel obvious rather than confrontational.

ではあるまいし vs ではあるまいか

Both ではあるまいし and ではあるまいか share the old-fashioned negative volitional まい, but their jobs are completely different.

ではあるまいし
it’s not like; it isn’t as if
Denies a hypothetical premise, then follows with a natural consequence.
子供(こども)ではあるまいし、自分(じぶん)でやりなさい。
You’re not a child, so do it yourself.
vs
ではあるまいか
isn’t it?; I wonder if it’s not ~
A rhetorical question or conjecture, often formal. The speaker suspects something is true.
これは誤り(あやまり)ではあるまいか。
Might this not be a mistake?

Quick contrast in one breath:

  • ではあるまいし → “Come on, it’s not like …” (dismissive, then a plain statement).
  • ではあるまいか → “Isn’t it …?” (thoughtful, rhetorical, often written).

If both translations seem possible, check whether the sentence ends with a question or a declarative conclusion. A question mark or a か at the end strongly suggests the conjecture pattern.

Common mistakes with ではあるまいし

高い(たかい)ではあるまいし、買え(かえ)ない。
金持ち(かねもち)ではあるまいし、そんな高い(たかい)(もの)買え(かえ)ない。
い-adjectives don’t attach directly to ではあるまいし. Rephrase with a noun like お金持ち(かねもち) (“rich person”) or use a clause: 高い(たかい)のではあるまいし is possible but awkward; a noun works better.
簡単(かんたん)ではあるまいし、やってみよう。
簡単(かんたん)ではあるまいし、そんなにすぐにはできない。
The second clause must logically follow from rejecting “easy.” “Let’s try” doesn’t fit. The natural follow-up is a warning about difficulty, not a call to action.
神様(かみさま)ではあるまいし、全部(ぜんぶ)知っ(しっ)ている。
神様(かみさま)ではあるまいし、全部(ぜんぶ)知っ(しっ)ているわけがない。
The pattern rejects the premise, so the conclusion must be a denial or a limitation, not an affirmation. Use わけがない or はずがない to match the dismissive tone.

A helpful practice method is to write a sentence with ではあるまいし, then try replacing the noun with an opposite idea (adult → child, expert → amateur). See how the follow-up sentence changes.

Is ではあるまいし on the JLPT?

N1
ではあるまいし is firmly a JLPT N1 pattern. It rarely appears before the advanced level.
🔹 recognise in reading passages and character dialogue
🔹 understand its dismissive, logical tone
🔹 choose the correct attachment (noun or な-adj stem) in grammar section questions

For test preparation, study the grammar point in full sentences. JLPT questions often test whether you understand the surrounding context—Is the speaker scolding, reassuring, or reasoning?—not just a dictionary meaning.

Practice questions for ではあるまいし

1 Use ではあるまいし in a sentence where you tell a friend not to panic over a small mistake. reassurance
2 Write a sentence where the rejected premise is an occupation (先生(せんせい), 料理人(りょうりにん), etc.) and the conclusion is about a reasonable expectation. job-based logic
3 Rewrite a direct command (e.g. “早く(はやく)準備(じゅんび)して”) by first inserting a ではあるまいし phrase to make it sound less harsh. softening
4 Compare ではあるまいし and ではあるまいか in your own example pair. Explain why the tone shifts. vs. まいか

Keep your first sentences simple. Once the structure feels natural, add more context so the nuance becomes clear.

Learning path for ではあるまいし

To learn ではあるまいし efficiently, start with its formation, then compare it with similar patterns, and finally practice in context.

1
Master the attachment: you can only use nouns or な-adj stems directly. For verbs, insert の. Write five correct attachments without checking a chart.
2
Contrast with ではあるまいか. Read several example sentences of each and label the speaker’s intention (dismissal vs conjecture).
3
Pick a scenario from daily life—a friend oversleeping, a colleague making an excuse—and construct a short dialogue where one person uses ではあるまいし to nudge the other toward a sensible action.
4
Take a sentence that uses ないでください or なさい and rephrase it with ではあるまいし to create a softer, more logical tone. Record yourself saying both versions to feel the difference.
  • ではあるまいか — because it shares the negative volitional まい but acts as a rhetorical question, not a dismissal
  • ではすまない — because it also deals with denying that a simple solution will work, often with a noun attachment
  • どうにもない — because it carries a similar “there’s no way” feeling, but in a resigned rather than dismissive tone
  • でなくてなんだろう — because it likewise uses a rhetorical structure to make a strong point, though about identity rather than premise rejection

Learn ではあるまいし with Hane

If you want to review ではあるまいし together with the related patterns above, Hane helps you practice Japanese in short, focused sessions.

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FAQ about ではあるまいし

What does ではあるまいし mean in Japanese?

ではあるまいし means “it’s not like; it isn’t as if ~” in Japanese. It is an N1 grammar point, and this lesson explains its formation, nuance, example sentences, common mistakes, and similar grammar.

Is ではあるまいし on the JLPT?

ではあるまいし is taught as N1 Japanese grammar in Hane's grammar lesson archive. Review it with examples, usage notes, and related N1 patterns.

How should I practice ではあるまいし?

Read several example sentences, identify the form before and after ではあるまいし, then make your own short sentences and compare it with nearby grammar points.

Practice this with Hane
Drill ではあるまいし 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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