Amy: Jewelry? Seriously? Sheldon, you are the most shallow, self-centered person I have ever met. Do you really think that another transparently manipul... Oh! It's a tiara! A tiara. I have a tiara! Put it on me, put it on me, put it on me, put it on me, put it on me, put it on me, put it on me.
Penny: You look beautiful
Amy: Of course I do. I'm a princess and this is my tiara.
Sheldon: You were right, the tiara was too much.

Look, Howard, I'd say there's lots of fish in the sea, but I've seen you dangle your hook in that water for years, do not throw her back.

Leonard

I mean, even Donkey Kong had Donkey Kong, Jr., so he could teach someone how to kidnap princesses and throw barrels at Italian plumbers

Howard

Sheldon: I don't think there's anything in this jewelry store that Amy would appreciate more than the humidifier that we were just looking at at Sears.
Penny: Oh, my God, now I know what I sound like to you when I say stupid stuff.

Leonard: I don't know what to tell you, buy her something.
Sheldon: How does that work?
Leonard: Well, you skip over any attempt to repair your emotional connection and you win back her affection with an empty financial gesture.

You know digital alcohol is not the solution.

Leonard

Sheldon: Oh, I see why you're confused. No, her news sounded important, but what your 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.

I'm telling you dude there's a seat on the Hogwart's Express with your name on it.

Raj

The Big Bang Theory Season 5 Episode 12 Quotes

Sheldon: Oh, I see why you're confused. No, her news sounded important, but what your 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.

I'm telling you dude there's a seat on the Hogwart's Express with your name on it.

Raj