Answer:
Three little letters, a paradox to some. The worse that it is, the better it becomes.
What is the thing that stays the same size, but the more it's used the more it decreases?
You can hold it without using your hands or your arms. What is it?
A hill full, a hole full; yet you cannot catch a bowl full. What is it?
Some live in me, some live on. And some shave me to stride upon. I rarely leave my native land. Until my death I always stand. High and low I may be found. Both above and below ground.
What did the piece of wood say when he saw the screwdriver and screws approaching?