Answer:
I jump when I walk and sit when I stand.
I plow and plow, but never sow. What am I?
You may enter, but you may not come in. I have space, but no room, I have keys, but open no lock. What am I?
What goes up and down but does not move?
If you have me you want to share me. If you share me you don't have me. What am I?
When is it bad luck to see a black cat?