He greeted all his guests with a fixed smile on his face.

他对所有的客人都以他的一贯笑容相迎。

《牛津词典》

I had to go through the rest of the evening with a fixed smile on my face.

我不得不带着一脸僵硬的笑容度过那晚余下的时间。

《柯林斯英汉双解大词典》

The boy would then fall to the grass, get up, without looking back at his mother, run as fast as he could, again, still with a smile on his face, as if nothing had happened.

然后，小男孩摔倒在草地上，再爬起来，不回头看他的母亲，再一次以最快的速度跑起来。他的脸上仍然挂着微笑，好像什么也没发生过。

youdao

Like he did on all of his makes, Stauskas came back down the court with a smile on his face, sharing the moment with the Wolverines fans who made the trip to North Texas.

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The mechanic is a tall wiry man with a youthful face and a ready smile.

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He is here with a smile on his face and he will do his best.

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