Sheldon: Hello?
Leonard: Oh, hey, where you been? We've been calling you for hours.
Sheldon: Oh, I'm sorry, my phone was on "airplane" mode.
Leonard: Why?
Sheldon: Because I was on an airplane. (makes confused gesture to Amy)

Sheldon: So that's all this day was? A plan to butter me up before delivering bad news?
Leonard: Come on, buddy.
Sheldon: No, I thought we were friends. You asked for a sip of my Icee. If you had your own straw, I might've said yes.

(Leonard standing outside the door to Sheldon and Amy's apartment)
Leonard: Help! Cinnamon's loose in the building!
Sheldon: (Inside) Amy, quick, lock the door!

Penny: I thought you were looking at a cliff on the beach.
Amy: We were, but Sheldon didn't like any of them. Some were too beachy, some were too cliffy.
Sheldon: And all of them were too outsidey.

Sheldon: Ladies.
Penny: What's up?
Sheldon: As you may know, I have been experimenting with elevated anxiety levels, and I thought what better way to increase my discomfort than to subject myself to an evening of tasteless, uncensored crotch talk.

Amy: Why'd you pop it?
Sheldon: Sorry, I was aiming for your heart.

Sheldon: Do either of you know Beyonce? I'd love her to get behind it.

Sheldon: Stephen Hawking is a genius. If he said 'no,' I wasn't going to waste time on her father.

Penny: I thought they fired you guys.
Sheldon: They did, but then they hired me back.
Leonard: Well, you better not be working on our project, because we're a team.
Sheldon: Leonard, there is no "I" in team. However, there is an "I" in "I'm working with the military and you're not." There's five of them, in fact.

Sheldon: So, did you defile my mother or not?

Penny: That's so funny. I never would have pegged you for a Pisces.
Sheldon: You're making it difficult to love you right now.

Amy: Well, for starters, there's nothing wrong with keeping our toothbrushes in the same holder.
Penny: Sheldon, what do you say to that?
Sheldon: I think we should see other people.

Sheldon: I suppose I could see myself in a scientific boyband. Of course I'd be the dreamy one and the smart one.

Leonard: That's not necessary.
Sheldon: It is. They're what hold back the urine and faeces.

Leonard: I'm a little nervous.
Sheldon: Well, get over it. Confidence is key in these situations.
Leonard: Right. *Pushes button*
Sheldon: You pushed it! Are you out of your mind?