Japanese with Manga
Learning through examples in manga

It's not like I'm a grade-schooler with 〜じゃあるまいし

Grammar Explanation: It's not the case with 〜ではあるまいし

Manga panel from からかい上手の高木さん showing example of It's not like I'm a grade-schooler with 〜じゃあるまいし.
からかい上手の高木さん » Volume 8 » Page 122

Seeing a frozen puddle on the ground, Nishikata is excited at the thought of picking it up and holding it. Takagi asks if this is what he’s thinking, and he quickly denies it.

西片(にしかた):
「そんな…　小学生(しょうがくせい)じゃあるまいし。」
“It's not like I'm some kind of...grade-schooler.”
高木(たかぎ):
「ふーん。ホントかな。」
“Hm, I wonder...”

Key Points

  1. 〜じゃあるまいし = it’s not like…

    • This pattern rejects a comparison or assumption.

    • Here Nishikata means “I’m not some little kid like that.”

  2. 小学生(しょうがくせい)じゃあるまいし

    • 小学生(しょうがくせい) is the comparison he rejects.

    • The implication is that getting excited over frozen puddles would be childish.

  3. The sentence omits the rest because it is obvious

    • The line does not fully spell out “I wouldn’t do that.”

    • Japanese often leaves the conclusion unstated when the intended meaning is already clear.

See Also