Answer:
What goes up and down stairs without moving?
The more holes you cover the lower I go.
Part carbon part water I am poison to the fishes. Many falsely claim my name I am the pause that refreshes.
I can run but not walk. Wherever I go, thought follows close behind. What am I?
Travel a mile and I will change, travel a million and I will end as I started. What am I?
I flow from the Homerβs mouth when he sees doughnuts.