吃大亏

lose out badly

吃小亏占大便宜。

No pain, no gain.

吃亏上当

be fooled

不让别人吃亏

not cause others to lose out

这样做他要吃亏。

He'll lose out if he does it that way.

过去劳动人民还吃了没有文化的亏。

In the past, workers' lack of education put them at a real disadvantage.

他们吃了经验不足的亏。

Their lack of experience worked against them.

我吃了他的亏。

I lost out to him.

他吃了不老实的亏。

His dishonesty came back to bite him.