I'm waiting for someone to call me back with a price.

我在等人回电话报价。

《牛津词典》

I looked back, half expecting to see someone following me.

我回过头去，想着可能看到有人跟着我。

《牛津词典》

Have you ever yawned in front of someone, only to have them yawn right back?

你有没有在别人面前打呵欠，结果对方也打呵欠？

youdao

The expression probably comes from the physical act of turning your back toward someone, instead of speaking to him face-to-face.

VOA: special.2009.12.13

Do you think in some ways it is back to you being confronted with the rights of animals, in some way someone has to be confronted with poverty.

您是否觉得某种程度上来说，这和,您当时面对动物权利的问题时一样，一些人也不得不直面贫困问题。

普林斯顿公开课 - 人性课程节选

because someone turned the gas off and turned it back on and then left.

因为有人把瓦斯关了以后，又打开，忘记关上就离开了。

Make sure 课堂 - SpeakingMax英语口语达人

Someone back in economy class had died, and we had to wait for a coroner.

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And just because someone tips back a few beers doesn't make them irresponsible.

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The risks were high that someone would back him into a corner, but the stakes were too high to do otherwise.

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