Answer:
I have one, you have one. If you remove the first letter, a bit remains. If you remove the second, bit still remains. If you remove the third, it still remains.
What has two heads but only uses one
What do birds say when they fly home?
Why doesn't anyone make belts of watches?
What do you call two witches who live together?
If a rooster lays an egg on the exact peak of a barn, which side does it fall?