All ears

e.g. You said you had something important to tell me. I'm all ears!

Meaning: eager to listen; sharply attentive; curious

Origin: The ear is the organ by which a person hears. So, if we figuratively say that you' re "all ears," it means that at that moment you' re keenly listening to whatever is being said. It's as if no other part of your body mattered except your ears. This idiom is about three centuries old.

指急切地想听。这个谚语已大约有三百年历史。