Howard: Women, you can't live with them. You can't successfully refute their hypotheses.
Sheldon: Amen to that.

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.

Howard: On the potty, what are you five?
Raj: It's a potty, what do you call it?
Howard: A toilet.
Raj: That's a little vulgar for the dinner table, don't you think?
Howard: And potty is okay?
Raj: Potty is innocent. Potty is adorable.
Howard: What do you do on the potty, wee-wee?
Raj: If I don't have to boom-boom.

Sheldon: I'd like you to meet Oppenheimer, Frisch, Panofsky, Feynman, Weisskopf.
Mary: Yeah, I get it. You got a lot of cats, and you gave 'em cute Jewish names.

Mary Cooper: Now, when you said on the phone he broke up with a girl, you meant an actual girl? Not something you kids whipped up in a lab?