Howard: Calm down. There's a theme to this weekend. We are going to Mexico in Feynman's van to stay at the vacation house Feynman bought with the money from his Nobel prize.
Sheldon: Viva la Imodium. Ay, ay ay!

Sheldon: En garde, Leonard. Prepare yourself for a rigorous touching.

Leonard: Look, even if it's not him, Amy's probably going to date someone at some point.
Sheldon: You really think so?
Leonard: Of course. She deserves to be happy.
Sheldon: How dare you!

Howard: Sheldon, instead of focusing on Amy dating other guys, maybe you should start thinking about dating another girl.
Sheldon: That's ridiculous.
Raj: Why? You never thought you'd end up in a relationship, and then you met Amy. Maybe there's someone else out there for you.
Sheldon: True, but Penny's married, and so is Bernadette. And your girlfriend has red hair and white skin, which really rubs up against my clown phobia.

Sheldon: Excuse me. I'm recovering from a recent breakup, and I'm told asking out another woman might make me feel better.
And as Ash Ketchum said to Pikachu, "I choose you."
Woman: What?
Sheldon: It's a Pokemon reference.
Woman: I don't know what that means.
Sheldon: Well, we gave it a shot.

Sheldon: Sorry, but when you make a discovery like this, you don't just take it down to City Hall. You tell the whole world. And so I'll say it in Latin or Klingon or smoke signals, if that's not cultural appropriation.
Amy: It is.
Sheldon: Okay, so not smoke signals.

Sheldon: Amy, I usually know exactly what to say. But in this moment I have no words.
I guess I'm overwhelmed by you. In a good way. Not in the elevator in the Haunted Mansion way. Even if I can't tell you now how I feel, I will spend my life showing you how much I love you.

Sheldon: (After Leonard whistles) First warning.

Sheldon: I don't understand why you're not enjoying this. Together, in this car, with my enhanced capabilities, we're like Knight Rider.
Leonard: Except in Knight Rider the car isn't a yammering sphincter.
Sheldon: You mock the sphincter, but the sphincter is a class of muscle without which human beings couldn't survive. There are over 50 different sphincters in the human body. How many can you name?
Leonard: I was wrong. This is exactly like Knight Rider.

Sheldon: (Speaking Chinese to Leonard).
Howard: You just called Leonard a syphillitic donkey.
Sheldon: My apologies, Leonard. I'm only as good as my teacher.

Sheldon: When was the last time you had your menstrual cycle?
Penny: Oh, I'm not answering that Sheldon.
Sheldon: I'm going to say in progress.

Sheldon: My mom bought me those pants.
Leonard: I'm sorry!
Sheldon: You're gonna have to call her.

Raj: You own the damn thing, just take a freaking sweater.
Sheldon: I didn't turn a profit last quarter by taking product off the shelves willy-nilly.

Leonard: Too casual?
Sheldon: For an audience with the queen, yes. For an evening of passing a bottle of fortified wine around a flaming trash can, you look great.

Sheldon: 50% of marriages end in divorce, but 100% of sundae bars end in happiness.