Penny: I think I'm gonna go for a run. You want to come?
Leonard: No, last time that old lady in the park kept screaming, "Watch out, he's right behind you."

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?

Sheldon: It's not my fault I'm bad at sharing; I skipped kindergarten.

Sheldon: If it's like your 3-D chess game, then you're out of your length, width and depth. Amy, get the Neosporin, somebody just got burned.

Raj: Hey, this pregnancy had an emotionally-needy third wheel way before you came along.