Knock knock. Who's there? Dew.

Dew who? Dew-n't worry, it's just a drop in.

Knock knock. Who's there? Wu

Wu who? Wu don't know, I'm having an identity crisis!

Knock knock. Who's there? Flake.

Flake who? Flake out, I'm tired of waiting!

Knock knock. Who's there? Sew

Sew who? Sew long, I've been trying to stitch together a decent joke.