有些人很健忘，听到的事情过了一秒就会忘记，还有的人在接受别人的指点或教导时根本不用心听。对于这类人来说，他人的话就像耳边风一样“从一边进，又从另一边出去了”。于是，我们用表达 in one ear and out the other 来形容人爱忘事或者不专心。
You'll have to write it down for me. You know what I'm like, in one ear and out the other.
I don't know why I bother. It's in one ear and out the other with you. I've told you so many times to take your shoes off when you come in.
I reminded him to pick me up at five o'clock, but as usual it went in one ear and out the other. In the end I had to take the bus.
另一个和“耳朵”有关的表达 have an ear for something 的意思是擅长学习音乐或语言等技能，一听就会。
I really don't have an ear for music. I don't know if something is out of tune or not – so please don't ask me to sing.
She's got a great ear for accents. She can tell you not only which city someone comes from, but also which part of the city they're from, just from the way they speak.