behave, act, treat (someone) to
彼は自分がすごい人でもあるかのように振る舞う。
He acts as if he were someone important.
どうして私のことを知らないみたいに振る舞うの？
Why are you acting like you don't know me?
彼女がこんな風に振る舞うとは奇妙だ。
It's strange for her to behave this way.
時々彼はまるで私の上司のように振る舞う。
Sometimes he acts as if he were my boss.
彼は堂々と振る舞う。
He carries himself with confidence.
年齢相応に振る舞うようにしなさい。
Act your age.
傲慢に振る舞うとそうなるのはわかっていたはずだ
You should have known that would happen if you acted arrogantly.
— 善き人のためのソナタ (2006)
私にも分からないダビドも娘の学校も―私を知らないみたいに振る舞う
I don't understand David or my daughter's school either—they act as if they don't know me.
— 嵐の中で (2018)
同様に振る舞う他のイベントでも結構です。
Other events that behave similarly are fine as well.
彼は人に公正に振る舞う。
He treats people fairly.
動物は本能のままに振る舞う。
Animals act on instinct.
あんな風に振る舞うなんて彼は気が狂ってるに違いない。
He must be crazy to behave like that.
そんな風に振る舞うとは彼は頭がおかしいにちがいない。
He must be crazy to behave that way.
そして心は時に夢の中のように振る舞う
And sometimes the heart behaves as though it were in a dream.
— オープン・ユア・アイズ (1997)
彼女は誰にでも常に礼儀正しく振る舞う。
She is always polite to everyone.
彼は年齢相応に振る舞う。
He behaves his age.