びる

JLPT Level: N1
Meanings

to resemble; to have the air of; to look like; to become (in appearance or manner)

to seem to be ~; to appear to be ~

to take on a certain air or quality of ~

Usage

名詞 + びる

形容動詞の語幹 + びる

Explanation
びる attaches to nouns or the stem of a na-adjective to describe gaining an appearance, air, or impression of something. It is not about changing physically through action, but about the perception of being or becoming. It often expresses a qualitative change in how one is perceived, rather than a literal transformation.
彼は大人びた話し方をする。
かれはおとなびたはなしかたをする。

He speaks in a mature, grown-up way.

彼女は子供っぽくなく、落ち着いた振る舞いをしていて大人びて見える。
かのじょはこどもっぽくなく、おちついたふるまいをしていて、おとなびてみえる。

She doesn’t act childish and, with her calm demeanor, looks grown-up.

若く見られたいなら、もう少し落ち着いた態度を取ればいい。
わかくみられたいなら、もうすこしおちついたたいどをとればいい。

If you want to look younger, you should adopt a more composed attitude.