I make the guard stand in his place, Spur the courier to run his race, The backbone of your backyard’s border, I denote what’s later in the order.

I’m a person, a fruit, a dollar, a river, and shoe polish, what’s my name?

With ink as black as night It has a pen But does not write.

When thunder speaks, I lose my nerve, I blink and stutter, as if unsure. Not out, not on, a pulse obscure, I warn you that your electricity may not endure.

I follow the sun when it slips from sight, I'm gloomy, obscure and not very bright, I’m feared by some, yet needed for rest, Name me, at hiding things I'm the best.