A sea diver is a real show off.
He showed everyone that he can hold his breath under water for 15 minutes.
I went to the diver and told him that i can be under water for double the time i.e 30 minutes.
He responded that he will give me 1000$, if i would be able to do it.
I won the 1000$.
What did I do ?
My first, though water, cures no thirst, my next alone has soul, and when he lives upon my first, he then is called my whole.
What am I ?