来源于生活的不仅只有艺术，还有习语。正是因为它们来源于生活，习语才更为人们所熟悉或接受，有的时候习语的使用会恰到好处，甚至有画龙点睛的效果。当把它们还原到实际生活中时，就会有一种跃然纸上的熟悉感。
习语 out of one's depth 也作 beyond one's depth，它的字面意思是”水深超过了某人的高度“，因此往往有溺水的风险，例如：I can’t swim, so I am not going out of my depth.I'm not a strong swimmer, so I prefer not to go out of my depth.
因此它常用来比喻超过了某人的知识或能力范围，或遇到难以对付的问题了，相当于 over one's head，但不是 out of one's head，因为当 out of one's head 作表语时，表示某人神经错乱等，例如：out of/beyond one's depth:看完这部电影，观众意识到拍喜剧电影超出了这位导演的深度。I asked Alex to consult on this project because it's a bit out of my depth.我请亚历克斯咨询这个项目，因为它有点超出我的能力范围。I was out of my depth in the advanced class, so I moved to the intermediate class.The conductor realized that playing the fugue at the right tempo was beyond their depth .指挥意识到以正确的节奏演奏赋格曲超出了他们的深度。A lot of the jokes went right over my head.I tried to take in what he was saying about nuclear fusion, but most of it went over my head.
He must be out of his head to have spent that much money on an old car!
他一定是疯了，花了那么多钱买了一辆旧车！
You must be out of your head to want to go there now!
其实 out of 本身的意思很多，其中有两个主要意思有点相反，一是表来源，意为”从，用…制作“，二是表脱离或离开，表示不在原状态或不再参与某事，因此不同的场合意思是不一样的，例如：I paid for the damage out of my savings.The dress was made out of velvet.Both she and her husband are out of work.
I got out of the habit of riding my bike to work.
我改掉了骑自行车上班的习惯。
因此 out of one's head 既可以表示脱离了某种状态，意为”神经错乱，疯了“等，又可以用来表示脱离脑海，在句中作状语，意为”离开，脱离“，例如：
I can't get that tune out of my head.
我忘不掉那个曲调。
You'd better put the idea of marriage out of your head.
你最好放弃结婚的念头。
词或词组辨析：
intermediate [ˌɪntəˈmiːdiət] 意为”中间的，中级的“等
