귀가 밝다 = to have good ears (lit. your ears are bright)

젊었을 때는 저도 귀가 밝았는데, 지금은 작은 소리는 잘 안 들려요 = I used to have good ears when I was young, too, but I can’t hear small sounds now.

귀를 기울이다 = to listen carefully, to pay attention (기울이다 = to tilt)

아이들이 선생님이 해 주는 이야기를 귀를 기울여서 듣고 있었어요 = The children were listening to the story their teacher was telling them with full attention.

귀에 대고 속삭이다 = to whisper into someone’s ears (대다 = to put close to, 속삭이다 = to whisper) 

귀에 대고 속삭이지 말고 크게 말해요 = Don’t whisper to each other secretly. Speak loudly (to everybody).)

귀(가) 먹다 = to be deaf, to be not able to hear

귀 먹었어? = are you deaf (why aren’t you listening to me)?
저 귀 안 먹었어요. 조용히 말해요 = I’m not deaf. Speak quietly

귀가 간지럽다 = to feel like someone is talking behind one’s back (간지럽다 = to feel itchy)

어쩐지 오늘 귀가 간지러웠어요 = No wonder my ears were itchy today (when you find out someone was talking about you)

귀가 얇다 = to be easily influenced by what others say (얇다 = to be thin)

그 사람은 귀가 얇아서 설득하기 쉬워요 = He is easily influenced by what people say so he’s easy to persuade.

귀에 못이 박히도록 (듣다) = to have heard something too much already (to hear something so often that a callus forms on your ear)

그 얘기는 귀에 못이 박히도록 들었어요 = I’ve heard that story so much. I don’t need to hear it again.