Knock Knock Jokes

Joke: Knock knock!
Who's there?
Suspense.
Suspense who?
...... Ah!

Joke: Knock knock!
Who's there?
The interrupting cow.
The interrupting c-
Mooooo!

Joke: Knock knock!
Who's there?
Billy.
Billy who?
Are you senile? I said Johnathon.

Joke: Knock knock!
Who's there?
Your girl
Your girl who?
How many girls do you have!?

Joke: Knock knock!
Who's there?
You know.
You know who?
Run Harry Potter!

Joke: Knock knock!
Who's there?
Interruption snail.
Interrupting snail who?
*10 seconds pass*
Snail!

Joke: Knock knock!
Who's there?
Ding dong!
Ding dong who?
Ding dong, I just found the doorbell.

Joke: Knock knock!
Who's there?
Europe!
Europe who?
No! You're a poo!

Joke: Knock knock!
Who's there?
John Smith Alexander Thomas Eisenhower William Joesph Harvey Jr. the third!
...
That's what I thought.

Joke: Knock knock!
Come in!
You ruined the joke!