Penny: Listen, Mom, I know you're nervous, but I promise you, no one is gonna judge you or this family.
Susan: Oh, I'm sorry. It's just we're meeting Leonard's parents for the first time, and-and they're academics and-and intellectuals, and I don't want them thinking we're white trash.
Randall: Well, what color trash do you think they'll believe?

Raj: Can we take a moment to discuss that I just lied to the government for you?
Howard: Yeah, I would not have done that for you.

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.

Sheldon: Do you think your father's doing unspeakable things to my mother?
Leonard: No.
Sheldon: Are you saying that because the things are unspeakable?
Penny: Your parents are old. Anything unspeakable was finished by 9:30.