Leonard: If you want help, just hire a grad student.
Penny: Maybe I could do it.
Sheldon: You, really? You can assess the quality of my work? Okay, um, here. I wrote this when I was five years old.
Penny: A proof that algebraic topology can never have a non self-contradictory set of abelion groups. Im just a blond monkey to you, aren't I?
Sheldon: You said it, not me.

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Howard: I'm not signing a prenup.
Penny: All right, Howard Wolowitz, listen up! You sign anything she puts in front of you, because you are the luckiest man alive. If you let her go, there is no way you can find anyone else. Speaking on behalf of all women, it is not going to happen, we had a meeting.

Amy: Sheldon told me he had a new assistant named Alex. He didn't mention that Alex was a girl.
Penny: Maybe he didn't notice.

Bernadette: How you doing, Howie? You feeling a little better?
Howard: Oh, a lot better, thanks. One sec. Listen close, I don't have a lot of time. I need you to go to my house. In my bedroom, you'll find a model rocket. I want you to take it and bring it back to your place.
Bernadette: Okay.
Howard: Step two, build a version roughly fourteen stories high. Fill it full of rocket fuel and come get me. I'll leave the door unlocked.
Bernadette: Howie, honey, maybe you should talk to someone, let them know you're having a little anxiety.
Howard: No, no, I'm fine. No anxiety. We should probably talk in code. From now on, frog is me, sandwich means you and lemon means rocket. So, come on, sandwich, build me a lemon 'cause froggy wants to come home.

Bernadette: Hey, Howie, how you feeling?
Wolowitz: Better. Much better. The other astronauts held me down, gave me a shot. Oooh. Attention, people of Earth. Tonight, there will be two moons in the sky.
Bernadette: Howie, stop that. NASA's watching this! Put your pants back on!