Answer:
What is the thing which, once poured out, cannot be gathered again?
Two in a whole and four in a pair. And six in a trio you see. And eight's a quartet but what you must get. Is the name that fits just one of me?
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard.
People like this usually live in rural areas, unless they are lucky enough to strike oil and move to Beverly Hills.
You’ll have me at night and if you remove the first letter I denote the top, such as on a train
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.