Howard: What's the matter, you chicken?
Sheldon: I've always found that an inappropriate slur. Chickens are not by nature at all timid. In fact, when I was young, my neighbor's chicken got loose and chased me up the big elm tree in front of our house.
Raj: Chickens can't climb trees.
Sheldon: Thank God.
Howard: Okay, I believe the chicken made you his bitch.

Sheldon: Like the proverbial cheese, I stand alone. Even while seated.

Leonard: When he wasn't happy, we wanted to kill him. There was even a plan. We were going to throw his Kindle outside, and when he went to get it, lock the door and let him freeze to death.
Sheldon: That seems like a bit of an overreaction.
Leonard: No, the overreaction was the plan to tie your limbs to four different sled-dog team and yell "Mush!"

Sheldon: If this is about the night the heat went out, there's nothing to be embarassed about.
Raj: It's not about that.
Howard: We agreed to never speak of it again.
Sheldon: So we slept together naked. It was only to keep our core body temperatures from plummeting.
Howard: He's speaking about it.
Raj: For me it was a bonding moment.

Leonard: A long time ago, I made a deal with Howard involving you.
Penny: Okay, I don't know where this is going, but tread carefully, because this may be the last conversation we ever have.

Sheldon: It was you. I touched you!
Penny: Happy Valentine's Day.

Howard: (Singing) Bernadette, I am so sorry for... trying to propose to you. Bernadette, you found it creepy, but... that's just the kind of thing I do...Aaaaaaaaahhh. I know now it's too soon to talk of love, it was just a crazy idea that came to me in my tub. Bernadette, give me one more chance, Sweet Bernadette. I'll get the hang of this thing they call romance, Sweet Bernadette. I dream to once again kiss your lips, Sweet Bernadette. Sincerely Yours, Howard Wolowitz! Bernadette. (Song Ends) Thank you, Cheesecake Factory.

Sheldon: Where's your notebook?
Penny: Um, I don't have one.
Sheldon: How are you gonna take notes without a notebook?
Penny: I have to take notes?
Sheldon: How else are you gonna study for the tests?
Penny: There's gonna be a test?
Sheldon: Tests. Here. It's college-ruled. I hope that's not too intimidating.

Howard: (To Bernadette) Come on, I don't wanna eat lamb stew with my mother. (To himself) Damn, was this close to the bra.

Sheldon: (Dictating) Research Journal, Entry One. I'm about to embark on one of the great challenges of my scientific career: teaching Penny physics.! I'm calling it "Project Gorilla".

Penny: I have to go to the bathroom.
Sheldon: Can't you hold it?
Penny: Not for 2600 years!

Raj: Here comes Kripke.
Leonard: Who's that with him?
Raj: I believe that's the president of the university.
Leonard: And the board of directors. Abort! Abort!
Sheldon: There is no abort.
Raj: How could you not put in an abort?
Sheldon: I made a boo-boo, all right?

Sheldon: I refuse to sink to his level.
Raj: You can't sink, with all that helium in you, you're lucky you don't flow away.

Howard: Just giving the lady the old tour of the salt mines.
Bernadette: (Giggling) He doesn't mean salt mines , he means where he works.

Howard: It's not enough you get the prom queen, you have to get the head of the decorating committee, too?