There is no such thing as a free lunch.

世上没有免费午餐之类的好事儿。

《牛津词典》

They say there is no such thing as a free lunch.

他们说天下没有免费的午餐。

youdao

It's an example of the law that there is no such thing as a free lunch: the cost of the local gain is a global loss-just as it often is.

这正是“天下没有免费的午餐”规律的一个例子：局部获利是以全局损失为代价的，很多时候情况恰恰是这样。

youdao

figuring out there is no such thing as a free lunch but Markowitz tells us that diversification is a free lunch.

知道世上没有免费的午餐这回事,但马科维茨称分散投资是免费的午餐

耶鲁公开课 - 金融市场课程节选

And as the saying goes, there is no such thing as a free lunch.

WHITEHOUSE: Town Hall on America��s Fiscal Future

Well, as the saying goes, it turns out there is no such thing as a free lunch.

WHITEHOUSE: Shared Responsibility and Shared Prosperity Town Hall

Devotees of the unlimited data plan, get real: there is no such thing as a free lunch.

FORBES: Verizon Makes Wireless Pricing Rational