Bernadette: Hey, we can make bad decisions.
Penny: Yeah. She had two kids back-to-back and I thought you'd like this, so we're off to a good start.

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Sheldon: Well, of course I'm worried about you, I want you to be safe.
Amy: And I want you to be safe.
Sheldon: I will be. I'll have my friends with me. If anything should go wrong, I can use them as human shields.

Sheldon: *knock knock knock* Dr. Wolcott? *knock knock knock* Dr. Wolcott? *knock knock knock* Dr. Wolcott? [sound of many locks clacking]
Howard: That's a lot of locks.
Leonard: Mm. That was a lot of knocks, they were made for each other.

Sheldon: Do you really know how to Riverdance?
Amy: You tell me.
Sheldon: I'm the only man you do that for.