Answer:
My teeth are sharp, my back is straight, to cut things up it is my fate.
I am a box that holds keys without locks, yet they can unlock your soul.
They have not flesh, nor feathers, nor scales, nor bone. Yet they have fingers and thumbs of their own. What are they?
There is a puzzle which can be asked all day with a different correct answer each time. What is the puzzle?
I am a span of time you can always see through I am also the timepiece with the most pieces. What am I?
What is always coming but never arrives?