Answer:
What can you hold in your right hand but never in your left hand?
How do you discover something that does not exist?
How do you blink twice without blinking twice?
What is the building that you leave without ever having entered.
What is as big as you are and yet does not weigh anything?
I appear in the morning. But am always there. You can never see me. Though I am everywhere. By night I am gone, though I sometimes never was. Nothing can defeat me. But I am easily gone.