Answer:
What starts with an "e" but only has a single letter in it?
What gets colder as it warms up?
People in love are often bound to this.
It weighs next to nothing but no one can hold it for long. What is it?
Even if you throw it away, it still comes back.
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.