Answer:
What is the word that even in plain sight remains hidden?
I'm tall when I'm young and I'm short when I'm old. What am I?
I am the kind of soda you must not drink. What am I?
I am an English word that is as long as I am valued. What am I?
What goes up a chimney down but can't go down a chimney up?
I am used for light yet I am solid. Without me you would feel enclosed. I hate being touched especially with a lot of force. I like to be in buildings.