Answer:
People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?
I pass before the sun, yet make no shadow. I'm all around you, but you cannot see me. What am I?
I tell people to be careful when handling boxes.
What goes through cities and fields but never moves?
I start with T end with T and within me is T.
Runs over fields and woods all day. Under the bed at night sits not alone, With long tongue hanging out, Resting at your feet until we go for a walk