Leonard: My mother's texting you?
Penny: Yeah. We've been talking a lot lately.
Leonard: Why? She sick of talking to the magic mirror on the wall?

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Bernadette: What about this?
Raj: Uh, okay. Uh, pull off the skirt, slap a lightning bolt on the front, and you got baby Flash. Ooh, stick a long sleeve under it. Boom, Baby Sheldon!

Sheldon: You're a good teacher. Your son is going to be lucky to have you as a father.

Leonard: Come on. You can build things. You were an astronaut.
Howard: That's true. You know, as a kid, I used to make model rockets. That'd be pretty cool to do with a son.
Sheldon: Model rockets. Finally, something interesting! What is your preferred mode of recovery?
Amy: Sheldon, we're helping our friends.
Sheldon: And we got to model rockets, yeah? It was a tedious road, but well worth the effort.
Amy: So, have you thought of any names?
Sheldon: Amy, we finally got to model rockets. Why are you turning back?