Penny: Listen, Mom, I know you're nervous, but I promise you, no one is gonna judge you or this family.
Susan: Oh, I'm sorry. It's just we're meeting Leonard's parents for the first time, and-and they're academics and-and intellectuals, and I don't want them thinking we're white trash.
Randall: Well, what color trash do you think they'll believe?

Susan: Very nice, Wyatt. And you wonder why this one turned out the way he did.
Randall: You see what I've gotta put up with.
Susan: What you've gotta put up with? Why did you have to go to jail?
Randall: It's called getting caught, Mother!

Stuart: Nice to see you again, Dr. Hofstadter. I'm, uh, Leonard's friend, Stuart.
Beverly Hofstadter: Nice to see you, too.
Stuart: Hi, I'm Stuart.
Alfred Hofstadter: Ooh, I'm Alfred, Leonard's father.
Stuart: Oh! Oh, hi. Uh, I'm sorry, did you two want to sit together?
Beverly Hofstadter: No!
Alfred Hofstadter: No!
Stuart: I was wondering why the front row was available.

Bernadette: Anybody have anything snarky to say about that? Didn't think so.

Mary Cooper: There's a lot of traffic. Are we gonna be okay?
Amy: You'll be at the airport an hour before your flight.
Mary Cooper: Good. Thank you.
Sheldon: Plenty of time for you to meet another geriatric boy toy.
Mary Cooper: Hey, I will not have you be disrespectful to me.
Sheldon: Yes ma'am.

Sheldon: So, did you defile my mother or not?

Sheldon: Leonard? Leonard?
Leonard: What?
Sheldon: You realize you and I could become brothers.
Leonard: We're not gonna be brothers. We're not gonna be step brothers. Go to sleep.
Sheldon: I hope you're right. 'Cause a grown man living with his brother and his brother's wife is weird.

Sheldon: You know, also, if they did have coitus, we'll all be needing a skilled psychiatrist.

Raj: Hey, make sure you tell him that you weren't home when he came by and that your Indian friend gave you the message the moment you stepped through the door.

Howard: Okay, sure, I can meet with you on Thursday. Caltech is fine. Yeah, and may I ask what this is about? (laughs) I may not?
Raj: (To Bernadette) That's what he said to me!

Wyatt: So how's the world of pharmaceuticals treating you?
Penny: Pretty good. I actually just got assigned a much better territory.
Susan: See what happens when you work hard?
Randall: Hey, she just sells drugs. I had to make 'em.

Alfred Hofstadter: You're a patient young lady.
Sheldon: Hey, hey! She's mine! Take a cold shower, grandpa!

Bernadette: Not just Leonard and Penny's love, but the love we have for them, as well as each other.
Sheldon: Speaking of love, STDs among the elderly are skyrocketing.

Alfred Hofstadter:: If I may, I can assure you, your mother and I did nothing more than share a cab and a conversation.
Sheldon: Did that conversation include the phrase "your genitals are a joy to behold"?

Howard: That's great, now they know where I live.
Raj: What are you talking about? They've always known where you live.
Bernadette: Yeah, if you want to go off the grid, you have to move out of your mother's house.