Answer:
I hold two meanings. With one I may be broken, with the other I hold on. What am I?
David's father has three sons: Snap Crackle and ?
I am always running but I never get tired or hot. What am I?
I belong to you but others use me more often than you do. What am I?
I am owned by the poor the rich does not need me. If you eat me you will die!
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.