Penny: Well you wouldn't have asked me either.
Leonard: I would have asked you. In my head. On the way home. While I was having a good cry.

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: I really did think you looked pretty.
Amy: You did?
Sheldon: Yes. So much so that I started to panic.
Amy: Well you can relax. Just because you think I look pretty doesn't mean we have to spend the night together.
Sheldon: Were you hoping we would because it's prom?
Amy: I'm always hoping. But tonight, I just wanted to have a nice time with you. Maybe dance with someone who has arms.

Sheldon: There's no denying that I have feelings for you that can't be explained in any other way. I briefly considered that I had a brain parasite, but that seems even more far-fetched. The only conclusion was love.

Stuart: Oh, so she's good enough for Howard but not for me?
Howard: Yeah.
Bernadette: Yeah. Go have weird relationships with your own mother and cousin. This is his turf.