Answer:
This is a dead giveaway
You fill it and it empties, A metaphor for plenty, Depending on what half you see, It's either full or empty
What word is the same written forward, backward and upside down?
What is seen in the water and in the sky? It is part of the rainbow and can be in your eye
The main difference between us and zombies
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?