Leonard: "Article 10, subsection C: If questioned, Penny may not say that everything is fine if it isn't.
Other unacceptable responses include: 'It's nothing', 'Don't worry about it', and 'I said it's nothing, don't worry about it'."

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.

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

Leonard: I would pull this car over and kick you out, but if Penny dumps me, you're all I got.

Sheldon: Amy is free. She had a harp lesson on Saturday, but it got canceled. Boy, when you take an interest in people, you really uncork a geyser of nonsense.

Bernadette: Things going well with you and Sheldon living together?
Amy: Better than ever. He asks about my day, takes an interest in my life. He's like my boyfriend in college, except he's real, so people can see him.
Bernadette: I've been seeing him for years. I'm still not convinced he's real.