When Leonard tells Sheldon he needs to use more honey than vinegar on Penny, he tries an experiment where he uses chocolate as positive reinforcement on Penny. Amazing.
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Penny and Leonard try and talk out their little awkward hookup they have in the season three premiere last week.
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Leonard and Penny drink some peppermint schnapps in an attempt to try and get a little sexual chemistry going on for their awkward sex life.
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Hairy Leonard is very eager to see Penny upon his return from their three month expedition and is a little upset at Sheldon for crashing their good makeup time.
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It looks like Leonard and Penny will make up for lost time when Leonard returns from his arctic expedition in the season three premiere of The Big Bang Theory.
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Sheldon and Penny will never get together. Jim Parsons says these characters are just too good of friends.
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Will Penny and Leonard get together or won't they? Fans of The Big Bang Theory will find out in season three.
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Penny gives Leonard a gift... a blanket with sleeves... as his going away present before he leaves to the North Pole.
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TBBT Quotes

Penny, there's only one cookie with something in the middle that solves life's problems, and that's an Oreo. Or a Nutter Butter, if you're in a pinch.

Sheldon

Penny: Here's a question-- as an alien pretending to be human, are you planning to engage in any post-prom mating rituals with Amy?
Sheldon: There are post-prom mating rituals?
Penny: Not always. Unless your date drives a van with an air mattress, then always.
Sheldon: Well, if it's part of the prom experience, then I'm open to it.
Penny: You're kidding.
Sheldon: I may be an alien, but I have urges.If Amy wants to copulate by firing her eggs into space, well, then, I will happily catch them with the reproductive sac on my upper flermin. I'm not the best at reading facial cues, but I can see that you're a little turned on.