Raj: I hope this isn't awkward. The last time we met, I kind of embarrassed myself.
Howard: Let's see if you can go two for two.

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.

Howard: I invented a game. Want to play?
Leonard: Sure.
Howard: It's called Emily or Cinnamon. I give you actual quotes I've heard Raj say, and you guess if he was talking to his girlfriend or his dog.

Bernadette: Does your mother call you every day at work to see if you had a healthy lunch?
Howard: My mother calls me every day at work to see if I had a healthy bowel movement.

Sheldon: They're very different. Physics answers the question: what is the nature of the universe? Geology answers the question: you know, what'd I just trip over?

Amy: What's going on?
Sheldon: What if there was something I wanted to do, but I was worried other people would think less of me?
Amy: Is that other person me, and does it happen in the bedroom, in which case I think I'm cool with it?
Sheldon: No. It's about working with Bert on - You know what? I'm not even gonna say it. I am just gonna say the letter it starts with and -"ology". G-- Oh, no, that's not gonna work.

Sheldon: I've been modeling different types of dark matter and the traces they would leave on the zircon inside your meteorite.
Bert: What's this one here?
Sheldon: That's actually a dark matter model of my own creation. I call it the Cooper Boson.
Bert: Cool. I got to name a rock once. I named it Moderately Sedimented Shale. Guess I kind of pooped the bed on that one.