He traced the line of her jaw with his finger.

他用手指顺着她的下巴外缘抚摸。

《牛津词典》

Her jaw was set in a determined manner.

她下巴紧绷着，一副决不动摇的样子。

《牛津词典》

Patsy had to clench her jaw to suppress her anger.

帕茜不得不咬紧牙关来压下怒火。

《柯林斯英汉双解大词典》

She wasn't eating. She had terrible stomach pains. She started clenching her jaw and grinding her teeth at night.

VOA: special.2010.04.22

In May 2009, Jackson privately purchased Rachel Alexandra following her jaw-dropping 20-length victory in the Kentucky Oaks.

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Her only visible reaction was the clenching and unclenching of her jaw.

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Lisa's daughter Talia already had privacy settings on her Facebook account but her jaw dropped at what Tom found on her Twitter account.

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