Doris

Knock Knock!
Doris.
Doris, who?
Doris locked, that’s why I had to knock!

Police

Knock Knock!
Who’s there?
Police.
Police who?
Police let us in; it’s cold out here.

George Washington

Knock, knock!

Who’s there?

George Washington!

George Washington who?

George Washington who?!! Didn’t you learn anything in history class?!!