Ron gave her a knowing smile.

罗恩向她报以一个会意的微笑。

《柯林斯英汉双解大词典》

When asked who sent them just give a knowing smile.

当人家问你是谁送的时，只要回以一个会意的微笑。

youdao

"You'll find out on Valentine's Day." he said with a knowing smile.

“到情人节那天你就会知道了。”他笑着说。

youdao

When asked if a woman could successfully juggle a career and a family, she offered a knowing smile.

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Things like the affectionate touch to your face, the knowing smile when you do something nice for someone, the tear in their eye when you are sad or have been hurt by life, the smile when you are happy and they are sharing in it, the arms that hold you close daily.

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This time, her smile was slow and deliberate a knowing, almost ironic smile, the kind of smile exchanged between conspirators.

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