Định Nghĩa và Ý Nghĩa của "[be] all ears"

What is the origin of the idiom "be all ears" and when to use it?

The idiom "be all ears" originates from the literal idea that when someone is fully engaged in listening, their ears become the primary focus of their attention. This expression is used to convey a person's eagerness and attentiveness to listen to someone else.