Bernadette: (Shouting from the bathroom) How many times do I have to tell you to replace the toilet paper when it's empty?
Howard: I'm in the middle of something.
Bernadette: So am I!

Bernadette: I think what we're all trying to say is that you don't seem to be remembering how traumatic the experience was for you.
Raj: Like how women often forget the pain of childbirth.
Mike Rostenkowski: Like a woman. Great analogy.

Professor Proton: Can I ask you a question?
Leonard: Yeah, sure.
Professor Proton: Why do you put up with Sheldon?
Leonard: Oh, you know because we're friends.
Professor Proton: Why?
Leonard: Wow, you ask really hard questions. Look, I know he can be aggravating, but what you have to remember is he's not doing it on purpose, it's just how he is. But he's also loyal and trustworthy and we have fun together.
Professor Proton: You know you're describing a dog?
Leonard: He did bite me once. But in his defense, I came up behind him while he was eating.
Professor Proton: They hate that.
Leonard: Sheldon is the smartest person I have met. He's a little broken and he needs me. And I guess I need him too.
Professor Proton: Why is that?
Leonard: Boy, you will not let this go, will you?

Howard: Hang on, I know a place where you could you stay and earn some money at the same time.
Stuart: Great!
Howard: I just have to warn you: it will involve humiliation, degradation and verbal abuse.
Stuart: So, what's the catch?

Sheldon: *knocks three times* Amy, Bernadette, Penny. *repeats three times*
Bernadette: He's never going to stop doing that, is he?
Amy: I don't mind. I'm hoping to put his love of repetition to good use someday.

Sheldon: Sheldon Cooper does not cry.
Howard: That's true, you'd rust.

Mike: I know I'm hard on you, but you're not the worst son-in-law in the world.
Howard: Mike, that's the nicest thing you've ever said to me.
Mike: Well, I'm drunk.

Howard: So you can never take it (the sweater) off?
Leonard: No.
Raj: Not even to sleep?
Leonard: No.
Howard: So you're just an idiot?
Leonard: It's called proving a point.
Howard: Is the point you're an idiot?

Raj: We have to go over some ground rules about Emily.
Howard: Like when it turns out she's made of rubber, I don't say anything?
Raj: She's very real.
Howard: That's what it says on the box. Right next to dishwasher safe.

Penny: (To Raj's dog) Bark once if you need me to call PETA.

Howard: My arm is feeling numb. *Howard rubs his right arm*
Bernadette: That's the wrong arm for a heart-attack, doofus.
*Howard switches to his left arm*

Amy: I don't know what made me think tonight would be any different.
Bernadette: Well just the fact you got him up here says a lot. To be honest, I bet Howie $200 that it wasn't going to happen.
Howard: I'm going to the Lego Store to get a big-ass R2D2.
Bernadette: See, it's not just Sheldon, they're all idiots.
Howard: She's right.

Raj: Sheldon, I think you might find the support you're looking for if you realize relationships are a give and take. She can only be there for you as much as you are for her.
Amy: Thank you, Rajesh.
Raj: And Amy, you need to be patient with Sheldon and stop pressuring him into accepting intimacy on your terms.
Amy: You should probably go.

Bernadette: Hey, Stuart.
Stuart: *startled* Hey.
Bernadette: Sorry, did I startle you?
Stuart: Yes, but at this point pretty much any customer does.

Penny: You really going to lie on the floor and pretend to be dead all night?
Stuart: What do you think I was going to do at home?