Leonard: We're going to Long Beach?
Sheldon: No, of course not. There's no Cousin Leo; there's no intervention. Focus, Leonard.
Leonard: Oh, come on.
Sheldon: We just leave the house on Friday night, and we return in the wee hours, emotionally wrung out from the work of convincing Leo to go back into rehab.
Leonard: So, he goes back into rehab?
Sheldon: Yes, but he can relapse if Penny ever invites us to hear her sing again

If influenza was only contagious after symptoms appear, it would have died out thousands of years ago. Somewhere between tool using and cave painting, Homo habilis would have figured out to kill the guy with the runny nose

Sheldon: Anyway, the housekeeper in the faculty residence didn't speak any English. When I finaly managed to convince her I was sick, she said, "Möchtest du eine Darmspülung?"
Penny: What does that mean?
Sheldon: Based on what happened next, I assume it means, "Would you like an enema?"

Leonard: Alright, get some rest and drink plenty of fluids.
Sheldon: What else would I drink? Solids? Gases? Ionized plasma?
Leonard: Drink whatever you want

Sheldon: Checkmate.
Leonard: Argh, again?
Sheldon: Obviously you're not well-suited for three-dimensional chess. Perhaps three-dimensional Candyland would be your speed

Leonard: Sheldon, don't you think you're overreacting?
Sheldon: When I'm lying comatose in a hospital, relying on inferior minds to cure me, these Jell-O cultures and my accompanying notes will give them a fighting chance

[at The Cheesecake Factory]
Penny: Why didn't you just have soup at home?
Sheldon: Penny, I have an IQ of 187. Don't you imagine if there were a way for me to have soup at home, I would have thought of it?
Penny: You can have soup delivered.
Sheldon: I did not think of that

The local cuisine was a little more sausage-based than I'm used to, and the result was an internal blitzkrieg, with my lower intestine playing the part of Czechoslovakia

Leonard: You speak English really well.
Dennis: So do you... except for your tendency to end sentences with prepositions.
Leonard: What are you talking about?
Dennis: That.
Sheldon: He's not wrong

Ladies and gentlemen... honored daughters... while Mr. Kim, by virtue of his youth and naivety, has fallen prey to the inexplicable need for human contact, let me step in and assure you that my research will go on uninterrupted and that social relationships will continue to baffle and repulse me. Thank you

Sheldon: Here's the problem with teleportation.
Leonard: Lay it on me.
Sheldon: Assuming a device could be invented, which would identify the quantum state of matter of an individual in one location and transmit that pattern to a distant location for reassembly. You would not have actually transported the individual, you would have destroyed him in one location and recreated him in another.
Leonard: How about that.
Sheldon: Personally, I would never use a transporter because the original Sheldon would have to be dissintegrated in order to create a new Sheldon.
Leonard: Would the new Sheldon be in any way an improvement on the old Sheldon?
Sheldon: No, he would be exactly the same.
Leonard: That is a problem

Sheldon [to Kripke]: Also, I am given to understand that your mother is overweight.
Raj: Oh, snap.
Sheldon: Now of course, if that is the result of a glandular condition and not sloth and gluttony then I withdraw that comment.

TBBT Quotes

Oh, Bernadette, please play my clarinet.

Raj's poem

Sheldon: I'll have a diet Coke.
Penny: Can you please order a cocktail? I need to practice mixing drinks.
Sheldon: Fine... I'll have a virgin Cuba Libre.
Penny: That's... rum and Coke without the rum.
Sheldon: Yes, and would you make it diet?