"there ain't no such thing as a free lunch" in Chinese (Simplified)
Definition
这句话的意思是，世上没有免费的东西；一切都有代价，即使看起来免费。
Usage Notes (Chinese (Simplified))
极为口语化，常用于提醒别人警惕“免费”事物背后的代价。一般不用于正式场合。
Examples
There ain't no such thing as a free lunch. If someone offers you something, they want something back.
**天下没有免费的午餐**。如果有人给你什么，他们也想得到回报。
My dad always says, 'There ain't no such thing as a free lunch,' when I want something for nothing.
我爸爸总说：“**天下没有免费的午餐**”，当我想要不付出得到什么时。
He learned the hard way that there ain't no such thing as a free lunch after joining that program.
他在参加那个项目后惨痛体会到**天下没有免费的午餐**。
If it sounds too good to be true, remember, there ain't no such thing as a free lunch.
如果听起来太好，记住：**天下没有免费的午餐**。
They offered free tickets, but there ain't no such thing as a free lunch—I had to fill out a long survey first.
他们提供了免费门票，但**天下没有免费的午餐**——我先得填写一份很长的调查表。
You can take those 'free trials,' but just know, there ain't no such thing as a free lunch in the end.
你可以试用那些“免费体验”，但最后还是**天下没有免费的午餐**。