Sheldon: Stop it both of you! All this fighting, I might as well be back with my parents!
*Imitating his Mom* Dammit, George! I told you if you didn't quit drinking I would leave you!
*Imitating his Dad* Well, I guess that makes you a liar, because I'm drunk as hell and you are still here!
*Imitating his Mom* Stop yelling, you're making Sheldon cry!
*Imitating his Dad* I'll tell you what is making Sheldon cry, that I let you name him SHELDON!

Sheldon: You can't make a half sandwich. If it's not half of a whole sandwich, it's just a small sandwich.

Sheldon: Leonard, when that woman moved in three years ago I told you not to talk to her, and now look. We're going to be late for the movies.

Rajesh: Excuse me but I don't think Penny is out of line at all. You don't own her. It's like my girl Beyonce says: If you like it you should've put a ring on it.

Raj: Sorry doesn't make up for the fact that I had to cook chicken and rice with this vegan guy. You know what vegan chicken and rice is? It's rice!

Leonard:What am I supposed to say? Sure, Penny, I'm cool with having your old boyfriend sleep in your apartment.
Leonard imitating Penny: Well, Leonard, it doesn't matter if you're cool or not, 'cause I'm penny and I'm pretty and I can do whatever the hell I want.

Sheldon: Where exactly does the half-sandwich come from? Are you giving me half of someone else's sandwich, or do I have to wait for someone in the restaurant to order the other half?

Penny: Wow, Sheldon, I cannot believe you made up your own game.
Sheldon: Oh, Research Lab is more than just a game. It's like the slogan says, the physics is theoretical, but the fun is real.

Sheldon: I should have asked for much more than a comic book and a robot.

Wolowitz: Do you think I'd have rather been with you or sitting around for hours listening to my mother saying "Have y'ever pee'd so much in your life?"
Rajesh: Oh, you are such a momma's boy.
Wolowitz: Don't bring my mother into this.
Rajesh: You brought your mother into this!

Penny: Oh, there it is again. You think I'm stupid.
Leonard: No, there's a difference between being stupid and acting stupid.
Penny: Oh, yeah? Well, there's a difference between being a jerk and being an ass.
Leonard: No, there isn't. They're synonyms.

Leonard: Well, I can't read your mind, Penny!
Penny: Really? Why not? You're so smart, and I'm so dumb.

Penny: Oh, thank you very much. Come back soon. With the other half of my tip.

Mrs. Wolowitz: Howard, answer the door! I'm busy!
Howard: I'm busy too. You answer it.
Mrs. Wolowitz: I can't! I'm on the toilet!
Howard: For God's sake, I don't need to hear that! Can't you just say, "I'm busy"?
Mrs. Wolowitz: I said I'm busy, but that wasn't good enough for you!
Howard: You know what? I hope it's one of those home invasion deals, and they shoot me in the head.
Mrs. Wolowitz: Well, if it's a home invader, don't tell them I'm on the toilet!

Penny: How is that not talking to me like I'm an idiot? It's my friend, it's my couch, and it's my freakin' life!
Sheldon: It's also your roll.