Answer:
It can be clear like water, but it burns like fire.
Not a comb or a brush but makes the hair feel plush. What is it?
What goes trough your head but you forget it like 3 days after?
What has roots that nobody sees, and is taller than trees. Up, up it goes, and yet it never grows.
What is it that given one, you'll have either two or none?
I never sleep yet sometimes I weep. I can get angry or just be happy. Wherever you go, I will follow. No matter what you do, I will be there. I cannot die. What am I?