Answer:
This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has handsΝΎ lacks a head but has a face.
I usually wear a yellow coat. I usually have a dark head. I make marks wherever I go.
In the land of the green glass door there are riddles but no answers, sheets but no blankets, and books but no words. Name something found in the land of the green glass door.
I'm full of holes, yet I'm full of water.
What can be swallowed, but can swallow you?
I run through hills. I veer around mountains. I leap over rivers. And crawl through the forests. Step out your door to find me.