Answer:
What is as big as you are and yet does not weigh anything?
When is homework not homework?
If you count 20 houses on your right going to the store and 20 houses on your left coming home, how many houses did you count?
Railroad crossing without and cars can you spell that without any R's
There are 5 sisters in a room: Ann is reading a book, Margaret is cooking, Kate is playing chess, Marie is doing the laundry. What is the fifth sister doing?
I only exist when you are here. Where you never were I can never be.