Answer:
who do you think you know but sometimes you don't
Many have heard it, but nobody has ever seen it. It will not speak until spoken to. What is it?
What goes further the slower it goes?
Gold in a leather bag, swinging on a tree, money after honey in its time. Ills of a scurvy crew cured by the sea, reason in its season but no rhyme.
It is a sound of empty, speak and it'll talk back plenty. But all the more you yack, you'll get the same words back.
What language does a billboard speak?