Sheldon: My girlfriend wanted to move in with me. Which was no doubt a ploy just to see my, excuse my language, bathingsuit parts.

Howard: Sheldon, I'm more than smart enough to take your class.
Sheldon: *Laughs* No.

Raj: Hello, Daddy.
Dr. Koothrappali: What did you say to your mother?
Raj: Nothing. I was just calling to check in, make sure she's doing okay.
Dr. Koothrappali: Well, after talking to you, she seems to think I'm some sort of playboy.
Raj: Really? I don't know where she'd get an idea like that.

Amy: It's a good thing I'm not wearing flag underwear right now, cause there's about to be a fire.

Raj: All this time, I never knew there were steam tunnels down here.
Amy: Most universities have them. When I was an undergrad, I spent three days in one pledging a sorority.
Raj: Did you get in?
Amy: No, they forgot I was there. But it really opened up my pores.

Penny: Bernadette's nickname for you is the Virgin Pina Colada.

Howard: I can't argue with him, it's right there on the screen. Austria does look like a wiener.
Raj: That's nothing. Dude, go check out how hung Florida is.
Leonard: I'm sure Mrs. Florida's walking funny.

Penny: Hi, wanna do yoga with me?
Leonard: Let me just have some coffee first and then I'll have the strength to tell you how much I won't be doing that.

Leonard: A butterfly could have gotten himself home from Arizona.

Sheldon: I'm sensing awkwardness. Am I right?
Amy: Yes.
Sheldon: Swish.

Penny: So you want me to be a teacher's pet?
Bernadette: Couldn't hurt.
Leonard: I don't know. Who here has ever been hurt because they were the teacher's pet?
*Sheldon, Amy, Howard, Leonard and Raj raise their hands*

Penny: Well, that's not good. You being blindly infatuated with me was the rock we were building this relationship on.

Raj: This is so messed up.
Emily: I know, I'm having the best time.

Penny: Bernadette's just parking the car.
Dan: Oh good. Bernadette. Cute, sweet, vicious, little Bernadette.

Dr. Koothrappali: I see you got engaged.
Penny: Yes, we did.
Dr. Koothrappali: Let me tell you a story.
Raj: Dad.
Dr. Koothrappali: Sorry. I'm sure you won't grow to hate each other.