Raj and Sheldon get into an argument when Raj is out on his blind date. Guess who she goes home with?
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Penny uses Raj and the guys as her test subjects as she practices making drinks. Here's a pic of her getting Raj liquored up.
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Penny practices bar tending on the boys in order to learn up for her new job that will help earn her some extra cash.
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Raj gets extremely nervous and anxious after his parents set him up for a blind date with a girl from his childhood.
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The Big Bang Theory Season 1 Episode 8 Quotes

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?

Leonard: Do you really need the Honorary Justice League of America Membership card?
Sheldon: It's been in every wallet I owned since I was five.
Leonard: Why?
Sheldon: It says keep this on your person at all times. It's right here under Batman's signature.