Leonard: Cinnamon, guess who just did it "human-style".

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?

Amy: I don't know what made me think tonight would be any different.
Bernadette: Well just the fact you got him up here says a lot. To be honest, I bet Howie $200 that it wasn't going to happen.
Howard: I'm going to the Lego Store to get a big-ass R2D2.
Bernadette: See, it's not just Sheldon, they're all idiots.
Howard: She's right.

Sheldon: What is your problem?
Amy: It's Valentine's day. We're supposed to be having a romantic weekend.
Sheldon: Oh, really? 'cause I remember you saying this trip was going to be something we could both enjoy. Did you mean that or were you just trying to trick me?
Amy: Fine, it's true. I deserve romance and I didn't know how else to make it happen.

Leonard: I'm not sure it's a good idea to take Penny to where wine comes from.