Answer:
What is it that you must give before you can keep it.
I can ruin your day, or darken your life. And while I'm expected, I'm never alright. I'm bad for business, and worse for your hair. Wherever I am, there's something not there.
It's equally comfortable in an orchestra and a geometry textbook. What is it?
What can't you see, hear or feel, until its too late. What shadows love, and shopkeepers hate?
I have an eye but cannot see, You'll head inside when you see me.
What did the piece of wood say when he saw the screwdriver and screws approaching?