Knock knock. Who's there? Dough.

Dough who? Dough-n't worry, I'm just here for the bread!

Knock knock. Who's there? Silence.

Knock knock. Who's there? Purpose.

Purpose who? That's what I've been asking myself for years.

Knock knock. Who's there? Sew

Sew who? Sew long, I've been trying to weave a good joke.