Answer:
I have married many women but have never been married. What am I?
I am easy to waste and unstoppable
I have 24 keys but cannot open any locks. Sometimes loud sometimes soft
A dagger thrust at my own heart dictates the way I'm swayed. Left I stand and right I yield to the twisting of the blade. What am I?
I have a straight back and sharp teeth to cut objects.
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.