mad ,crazy相同之处:1两个单词都有疯狂,着迷,酷爱的意思.
I am mad about her.
I am crazy about her.
2.两个单词都有精神错乱,疯的意思.
I saw a mad man in the hospital.
I swa a crazy man in the hospital.
不同之处:mad 有生气,愤怒的意思,(在美国人口语中,这个词常挂在嘴上表示生气.跟"angry" "furious"是同意词.
My brother made me so mad.
insane似乎程度更高:
insane
[in5sein]
adj.
患精神病的,精神病患者的,极愚蠢的
insane
in.sane
AHD:[¹n-s³n“]
D.J.[in6sein]
K.K.[!n6sen]
adj.（形容词）
Of,exhibiting,or afflicted with insanity.
精神病的：精神错乱的,显示出或受精神病折磨的
Characteristic of or associated with persons afflicted with insanity:
精神病患者的：为精神病患者所特有的或与之相关联的：
an insane laugh; insane babbling.
疯笑；疯言乱语
Intended for use by such persons:
用于此类人的：
an insane asylum.
疯人院
Immoderate; wild:
疯狂的：过度的；狂暴的：
insane jealousy.
疯狂的妒忌
Very foolish; absurd:
蠢极的：非常愚蠢的；荒唐的：
took insane risks behind the wheel.
在车辆后面极蠢地冒险