insanity

医生诊断他患有严重的精神错乱。

The doctor diagnosed him with severe ___insanity.

在这种大热天穿毛衣出门简直是疯了。

It's pure ___insanity to wear a sweater in this scorching heat.

他认为在暴风雪中开车去爬山是一种疯狂的行为。

He thought driving up the mountain in a snowstorm was complete ___insanity.