Halloween. Puzzle

Halloween
Halloween

THE END

PUZZLE

It runs and runs,
But it will never run out.
It flows.
Who knows
What I am talking about?

My face is black,
As black as night.
On it with chalk,
All pupils write.
All right.

It is running
Night and day,
BUT IT never
Runs away.

NEVER PLANTED,
STILL IT GROWS.
WHAT IS THE ANSWER?
NOW WHO KNOWS?

What has four legs
But is not an animal?

I am white
I am good to drink.
What am I?

I am yellow,
I am made from milk,
You eat me with bread.

I am big.
I am in the sky
I give light.
What am I?