She stood before him, at the end of her speech, with her teeth clenched, her cheeks flaming.

她讲完话，站在他面前，咬紧牙关，双颊通红。

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Alex clenched her fists and gritted her teeth.

亚丽克斯握紧拳头，咬紧牙。

《柯林斯英汉双解大词典》

Her pen was clenched between her teeth.

她咬着笔。

《牛津词典》

Edi clenched her teeth.

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