Leonard: Buddy, buddy, listen, nothing bad is going on, she just she just didn't want you to know that the work on her apartment was finished a couple weeks ago.
Sheldon: I don't understand.
Leonard: She's enjoying living with you and she didn't want it to end early.
Sheldon: So, she's deceiving me in order to spend more time with me?
Leonard: Yes.
Sheldon: Oh. Well, I feel both flattered and hurt. Like when people say I look like that skeleton from Nightmare Before Christmas.
Raj: Oh my God, that's who you look like.

Bernadette: Anybody have anything snarky to say about that? Didn't think so.

Sheldon: Well, this is highly insulting.
Amy: Sheldon, don't overreact.
Sheldon: I'm the child she was worried about? I have a brother and sister whose combined intellectual wattage couldn't power a potato clock ... if I spotted them the potato.

Sheldon: It says here that up to 80% of new mothers experience baby blues. And that the best thing to do is reassure them that they're doing a good job. Bernadette, you are doing a good job.
Bernadette: Thank you, Sheldon, I'm feeling better now.
Sheldon: Thank you, Internet. I'm telling you, with the right YouTube video, I can give Howard a vasectomy.

Amy: Sheldon, that's enough.
Sheldon: Oh, yeah, no, fine. Let's just agree that both creations are special in their own way and it is foolish to try and compare them. Although, we didn't need to have sex with Howard for ours, so we win.

Raj: Yeah, this military guy showed up at Howard's door. He was terrifying.
Sheldon: Oh no, what did he say?
Raj: He gave me his business card and asked me to please pass it along to Howard.
Sheldon: That doesn't sound terrifying.
Raj: Not to a white guy born here, no. To a brown guy whose name has a lot of syllables in it - terrifying.

Raj: If we're all gonna die, why am I eating so much kale?

Penny: She said not to come. It's gonna be a while.
Amy: (sighs) Well, first deliveries can be slow.
Sheldon: I am starting to rethink the Flash onesie I bought this kid.

Sheldon: We don't need Howard's cousin, no. We have me.
Leonard: You're not a lawyer, Sheldon, you're just a know-it-all.
Sheldon: I am not a know-it-all. I'm a person who knows lots of things and likes to correct other people when they're wrong.
Leonard: That's the definition of being a know-it-all.
Sheldon: Or in German, a Besserwisser.

Penny: Oh God, I feel so bad, I just lied to her.
Amy: Oh, but you did it so well. That's amazing! It's like watching a sculptor, but your clay was lies.

Amy: Aww, I remember signing our first Relationship Agreement.
Sheldon: You seem to be forgetting the "no nostalgia" clause.

Sheldon: Oh, you know. The Lone Star state. That should be its Yelp rating.

Colonel Williams: I'll cut to the chase. The Air Force believes there's an application for this technology, and we're interested in funding your research.
Howard: Well, thanks, but you should know we're a little concerned about this being used in weapons.
Colonel Williams: Oh, well, let me put your mind at ease. What we use it for is none of your business.

Sheldon: No matter where I am, this will always be my spot.

Bert: Okay, well, thanks for coming by. You're nice people.
Penny: Well, so are you. In fact, you know what? We will never take you for granite. Did you get that? Granite? A little geology joke.