I feel rotten about leaving them behind.

我丢下他们不管，感到很惭愧。

《牛津词典》

When we feel offended by someone, we can tell him to his face instead of complaining behind his back.

如果你觉得被冒犯了，可以当面告诉对方，而不是在他背后抱怨。

youdao

I feel as if something's behind me all the time.

我总觉得好像有什么东西一直在我身后。

youdao

There is still a lot of apprehension. Consumers definitely feel that the worst is behind us, but we still have a ways to go,"

VOA: standard.2009.08.25

So you did all that but still feel behind the curve?

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