Answer:
Each morning I appear to lie at your feet, all day I follow no matter how fast you run. Yet I nearly perish in the midday sun.
What has a spot and is very bright, is sometimes, red, white, blue, yellow or green and is often blinding.
What can be heard and caught but never seen?
What goes further the slower it goes?
As soft as silk, as white as milk, as bitter as gall, a thick green wall, and a green coat covers me all.
What language does a billboard speak?