Her face was a cold blank mask.

她装出一副冷冰冰毫无表情的样子。

《牛津词典》

She stared at me with a blank expression on her face.

她木然地盯着我。

《牛津词典》

The third one sat quiet with a blank stare on her face and didn't say a thing for a few minutes.

第三个女号安静的坐在一边，两眼空洞什么也没说。

youdao

She glanced up, her face perfectly blank.

NEWYORKER: Sweetheart Sorrow

As he begins to backtrack, she jolts upright, stares back in shock, then in mock shock, shifting in subtle increments until she smiles, lets her face go blank again, and leans back into his arms with relaxed panic, a twenty-sided facial expression that should earn Lauren Graham a special Emmy.

NEWYORKER: Warming Trend

Playing quietly, Wiig is a decent and likable actress, but, for fans of her wild side, she seems diminished, her face a little blank.

NEWYORKER: The Better Life