screen

n. 屏,幕,银幕,屏风
v. 选拔,掩蔽,遮蔽

You can't screen your children from the real life forever.

你不能永远护住自己的子女，不让他们接触现实生活。

His job at the bank was just a screen for his life as a spy.

他在银行的工作仅仅是他当间谍的一种掩护。