Answer:
lighter than feather and softer than silk yet the strongest man in the world cannot hold me for more than a few minutes.
I go in dry and come out wet. The longer I stay in the stronger my surroundings get.
I am the key that is the hardest to turn
He has married many women, but has never been married. Who is he?
What is harder to catch the faster you run?
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.