Answer:
I reach for the sky, but clutch to the ground. Sometimes I leave, but I am always around
Nothing specific, but more than a few. This many clustered, together will do.
What object has keys that open no locks, space but no room, and you can enter but not go in?
What is in seasons, seconds, centuries, and minutes, but not in decades, years, or days?
It weighs next to nothing but no one can hold it for long. What is it?
What language does a billboard speak?