Because they are humerus
Names
She had no arms Knock knock. Who's there? Not Sally. What did Sally get for her Birthday? We don't know, she didn't open it yet.
Because if it did, we'd have sent foreign aid by now.
cacawatches
He lost his sense of humerus.
Because its humerus!
A hot rod. NOTE: When I was about 5, I thought this was the funniest joke on earth.