成语 wet behind the ears 直译是“耳朵后面还是潮湿的”，它的真正含义是“乳臭未干、初出茅庐”，形容年轻人“少不更事，缺乏经验”。据说这个成语源于胎生动物，如牛、羊刚生下来的时候全身湿漉漉的；虽然它们的身体很快就干了，但是耳朵背后却还是湿的。
Simon has just left school and is still wet behind the ears.
西蒙刚从学校毕业，还没什么社会经验呢。
Sarah knows the theory of the job, but when it comes to practical experience, she’s still wet behind the ears.
莎拉理论上知道这份工作该怎么干，但要付诸实践时，她可没有什么经验可谈。
The committee took no notice of what Peter said; obviously they thought he was still wet behind the ears.
委员会对彼得说的话不屑一顾，显然他们认为他缺少经验。