Answer:
I am round as a bowl, deep as a tub, but all the world's water couldn't fill me up.
It's been around for millions of years, but is never more than a month old. What is it?
He has one and a person has two. A citizen has three. And a human being has four. A personality has five. And an inhabitant of earth has six.
It's like food but water kills it. What is it?
What can you catch but not throw?
It rows quickly with four oars but never comes out from under his own roof. What is it?