Answer:
What comes down but never back goes up?
When this is found in a road you are forced to make a decision.
There are four of these, but everyone's favorite seems to be spades.
What has thousands of ribs and two backbones?
What goes trough your head but you forget it like 3 days after?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.