madman

n. 疯子,精神病患者

They must think you are a madman if you tell them you want to cross the Pacific on a raft.

如果你告诉他们你要乘木筏横渡太平洋，他们一定会认为你是个疯子。

A madman mutilated the painting by cutting holes in it.

有个疯子破坏了那幅画，在上面划了许多窟窿。