Answer:
What is the word that even in plain sight remains hidden?
I occur twice in eternity. And I'm always within sight.
I run cold and hot, I look blue but am red. What am I?
What leaps one time out of four?
Made of ten but two we make, When assembled others quake, Five apart and we are weak, Five together havoc wreak. What are we?
A little house full of meat, no door to go in and eat.