She smiled at him and he smiled back.

她冲他笑笑，他也冲她笑笑。

《牛津词典》

He smiled and I smiled back. As you do.

他微笑，我也报以微笑。真所谓礼尚往来。

《牛津词典》

I smiled at her. She smiled back at me.

我朝她微笑，她也向我微笑。

youdao

And Everett smiled back at the sick old man.

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And when they smiled back, which they did suddenly, they displayed rows of perfect teeth.

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We made eye contacts with the audience, and they smiled back at us.

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The federal police officers in the back smiled and waved and the truck slowed, letting her pass.

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