An open mouthed smile, where the lips are stretched and the teeth are on display, exudes confidence, warmth and a positive energy.

张开嘴的大笑，嘴唇向外扩张露出牙齿，这样的笑散发出自信，热情和积极的能量。

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He straightened up and looked at me, open-mouthed.

他直起身子看着我，嘴大张着。

《柯林斯英汉双解大词典》

"I used to stare at them in restaurants, open-mouthed until my little brother said 'er, Andrea, don't do that,'" she says, emitting a short burst of self-mocking laughter.

“我经常在饭店里张着嘴，呆呆的看着他们，直到我哥哥说‘别这样，安德丽亚！’”她一边说，一边自嘲的笑了起来。

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Connie was open-mouthed and close to tears when Norton announced the result after more than two million votes.

BBC: NEWS | Entertainment | Connie wins Maria talent contest

The hallmarks of the Furienmeister are open-mouthed, long-limbed figures, swirling in clouds or robes that give the impression of lightness or flight.

ECONOMIST: Master of the furies

She was gray, breathing fast, her body heaving with each open-mouthed gasp.

NEWYORKER: Letting Go