not born yesterday

基本解释

I would like to mind you I was not born yesterday.
我想提醒你，我并非是个乳臭未干的孩子。
He knows how to solve such a problem. He was not born yesterday.
他知道如何去处理这种问题，他可不是乳臭未干的小孩子。
The world was not born yesterday, nor will likely be ruined tomorrow.
世界不是昨天才诞生，也不会明天就毁灭。

Yet Russians were not born yesterday: opinion polls show that most believe the government knows all that there is to be known about the disaster, but has no intention of making it public.
ECONOMIST: Russia's sunken submarine
In sum, it appears Googleopoly has grown so accustomed to being able to dictate to everyone which information they should accept as most relevant, that they have scant self-awareness when their message does not pass the laugh test with a principled audience that was not born yesterday.
FORBES: Google's Extreme Makeover of its Heritage