Knock knock. Who's there? Implication.

Implication who? I thought that was implied.

Knock knock. Who's there? You tell me.

You tell me who? No, *you* tell *me* who's there. I'm the one knocking, how should I know who's inside?

Knock knock. Who's there? Dough.

Dough who? Dough-n't worry, I knead to come in.

Knock knock. Who's there? Egg

Egg who? Egg-cuse me, I'm cracking under the pressure to make a good pun.