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to behave; to conduct oneself; to act
to treat (someone) to (food or drink); to entertain (e.g. to lunch)
彼は紳士のように振舞うことができる。
He can behave like a gentleman.
お客様に料理を振舞って喜ばれた。
I treated guests to food and they were pleased.
大人として責任ある振舞いを心がける。
I try to behave responsibly as an adult.