Knock Knock!
Who's there?
Ivan.
Ivan who?
Ivan to suck your blood!!
Knock Knock!
Who's there?
Theodore.
Theodore who?
Theodore is stuck and it won't open!
Knock Knock!
Who's there?
Moo.
Moo, who?
Well, make up your mind, are you a cow or an owl?
Knock Knock!
Who's there?
Cargo.
Cargo who?
Cargo beep! beep!