Answer:
What goes up but never goes down?
I have joy in bringing two together, but darning my existence! My life hangs by a thread, filled with ups, downs and resistance!
Blind but cruel.
A blue house has blue bricks; a yellow house has a yellow bricks. What is a green house made of?
What can you hold in your left hand but can never hold in your right hand?
What is often on the ground getting stepped on by others, but you don’t have to wash it because it never get dirty, in fact you couldn’t wash it even if you tried?