Answer:
When I point up, it's bright. When I point down, it's dark. What am I?
My first half means container. Not a lot of people understand my language.
So simple, that I can only point. Yet I guide men all over the world.
I have roots nobody sees. I am taller than trees. Up up I go but I never grow.
I am an English word that is as long as I am valued.
What is always coming but never arrives?