Answer:
I'm full of holes, yet I'm full of water.
The root tops the trunk on this backward thing, that grows in the winter and dies in the spring.
Voiceless it cries, wingless flutters, toothless bites, mouthless mutters.
A horrid monster hides from the day, with many legs and many eyes. With silver chains it catches prey. And eats it all before it dies. Yet in every cottage does it stay. And every castle beneath the sky.
What is the thing which, once poured out, cannot be gathered again?
People take me on walks and I run and have fun. What am I?