Answer:
What three letters change a boy into a man?
You do not want me when you donβt have me, but when you have me you donβt want to lose me. What am I?
I am what one cannot keep, two cannot hold, and three cannot destroy. What am I?
What runs around the whole yard without moving?
I break down buildings, I crumble mountains but you can't see me. What am I?
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.