PID控制器是控制工程师的通用工具，适用于各种各样的过程。

I don’t care if you’re a fan or not, I’m still gonna be me.

No matter how tough the loss, defeat is not final until you stop trying.

We must balance the need for energy with the need to protect the environment.

解释：乌鸦聚集在一起，虽然看上去很和好，实际上并不亲密；不慎重地结交朋友，虽似牢固，终必破裂。