Answer:
What is so fragile that saying its name breaks it?
What can run but can’t walk?
What is that which, though black itself, enlightens the world without burning?
Weight in my belly, Trees on my back, I travel fast in my place, but feet is a feature I lack
You will find me with four legs, but no hair. People ride me for hours, but I don't go anywhere without needing to be tugged. Jerked or turned on, I always manage to be ready for work.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?