Why did Sally fall off of the swing?
Because she has no arms.
Knock knock.
"Who's there?"
Not Sally.
Sally and the Swing
Categories
Explanation
Experiment
Explain Bear
Listen here, you chucklehead. You didn't think this one through, did you? Sally fell off the swing because she has no arms and cannot hold on. Then, in the knock-knock part, they are making it clear that Sally is not coming to the door because she cannot, and is maybe dead, because of the lack of arms. It's not that difficult, even for a smoothbrain like you.