Answer:
How can a pants pocket be empty and still have something in it?
What cleans as it gets dirty only to get clean the more you use it?
There are 7 birds in a tree. A hunter shoots one bird down. How many birds are left in the tree?
What can be any size or shape and gets bigger the more you take from it?
What is at the end of every rainbow?
What is full of holes but still holds water