Penny: Sheldon, what is wrong with you?
Sheldon: Not much. Although, I can’t be faulted for being overly fond of koala bears. I don’t know what it is, when they start munching on eucalyptus I just melt inside.
Penny: Okay, Amy just told you some exciting news and you acted like it was no big deal.
Sheldon: Oh, I see why you’re confused. No, her news “sounded” important, but what you’re forgetting is, it was an achievement in the field of biology, that’s all about yucky squishy things.
Penny: Honey, she’s upset! You’re her boyfriend, you have to at least try to be excited by the things she’s excited by.
Sheldon: What if they simply don’t excite me?
Penny: Well, just smile and think about koalas.
Sheldon: She’d see right through that! We go to the zoo all the time, she knows my koala face. If, for future reference it’s this