Answer:
What can be swallowed, But can also swallow you?
Goes over all the hills and hollows. Bites hard, but never swallows.
Two little holes in the side of a hill. Just as you come to the cherry-red mill.
What can answer in any language? What can speak without a mouth? What can sing without an ear?
A circle of stones, never in rows. Stacked one on the other, mystery it sows. What is it?
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?