expression, godan verb (-ru)
wear a mask
Literal meaning: to put on a physical mask, such as at a costume party or in a play.
ハロウィンで仮面をかぶってパーティーに行った。
I wore a mask and went to the Halloween party.
expression, godan verb (-ru)
hide one's true intentions; put on a false front
Idiomatic use: to pretend to be someone you are not, or to conceal your real feelings or motives.
彼はいつも仮面をかぶっていて、本心がわからない。
He always wears a mask, so I can't tell what he really thinks.