Answer:
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?
What is the freedom of birds and the pen of old men?
Sleeping during the day, I hide away. Watchful through the night, I open at dawn's light. But only for the briefest time, do I shine. And then I hide away. And sleep through the day.
There is an ancient invention. Still used in some parts of the world today. That allows people to see through walls.
You throw me out when you want to use me and you take me in when you don't want to use me. Who am I?
Why did Superman flush the toilet?