Leonard: Hey, you guys let Stuart live with you. Why not Raj, too?
Howard: What-what are you doing? I-I-I schlepped the baby over, I brought imported beer. Why don't you like me?

Howard: You know, I'm really glad you decided to learn Mandarin.
Sheldon: Why?
Howard: Once you're fluent, you'll have a billion more people to annoy instead of me.

Bernadette: Maybe we should get one of those machines to help her up the stairs.
Howard: You mean a forklift?

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

Amy: What is this?
Sheldon: I'm mapping basic topics of conversation and with whom they can be discussed.
I call these circles "Zones of Privacy". Don't Google that unless you want to see pictures of people's genitals.

Bert: I met her on G-Harmony. That's a Web site for geologists to find love.
Amy: That's a real thing?
Bert: Yeah. Their slogan is "We're all about dating and not the carbon-14 kind".

Sheldon: Two years ago I got my driver's license.
Amy: What? Why didn't you say anything?!
Sheldon: I like being chauffeured around. It makes me feel important.
Amy: So when I got up at 4:00 AM to drive you across the desert to an antique train museum, I didn't have to?
Sheldon: No, you didn't. But keep in mind, I felt extremely important.