Answer:
What two keys cannot open any door?
It rows quickly with four oars but never comes out from under its own roof. What is it?
I have a head, tail, but no arms and legs. What am I?
I have a name that's not mine and no one cares about me in their prime. People cry at my sight and lie by me all day and night.
I run smoother than any rhyme, I love to fall but cannot climb. What am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.