an insane person

• 精神错乱的人

an insane person的用法和样例：

例句

1. Don't let such an insane person drive the car, or you'll regret it.
   不要让这样一个精神错乱的人开车，否则你会后悔的。
2. And now, some days of bitter grief having elapsed, an observable change came over the features of the mental disorder of my friend.
   悲痛欲绝的几天过去了，我朋友精神错乱的表现有了可察觉得出的变化。