Answer:
Once you know it exists, it no longer exists. What is it?
What is it that after you take away the whole, some still remains?
A blue house has blue bricksΝΎ a yellow house has a yellow bricks. What is a green house made of?
Watches students at the prom to make sure there's no funny business.
Timid or weak people are said to not have these.
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?