Answer:
What kind of dog keeps the best time?
I dig out tiny caves and store gold and silver in them. I also build bridges of silver and make crowns of gold. Sooner or later everybody needs my help yet many people are afraid to let me help them.
I twist and turn and leaves a loop
I sit in a corner while travelling around the world.
What is easy to spot but hard to find?
What did the piece of wood say when he saw the screwdriver and screws approaching?