Knock Knock! Who's there? Zany Zany who? Zany body home?
Knock Knock! Who's there? Justin Justin who? Justin time for dinner!
Knock Knock! Who's There? Figs Figs who? Figs the doorbell, it's broken!
When Chuck Norris was a child, he would play with real logs instead of Lincoln logs.
Knock knock. Who's there? Sarah. Sarah who? Sarah problem here?
Knock Knock. Who's There? Justin. Justin who? Your justin time to wipe my ass!
What is black and white and red all over? (A panda bear with a sunburn!)
Fast way to screw up someone's Knock Knock joke...? "It's open."
Knock knock Who's there? Double. Double who? W!
Knock,Knock, Who is there? Pen! Pen who? is...