Leonard: And this is a high-pulse laser with a BBO crystal. It's pretty cool. It emits photons in discrete bursts.
Beverly Hofstadter: Huh. Very impressive.
Leonard: But?
Beverly Hofstadter: But what, dear?
Leonard: Oh, I don't know. It's just, usually there's a "but" followed by something that makes me feel bad.

Penny: Or you accomplished something great, and she's genuinely proud.
Leonard: [taking Penny's wine glass] Yeah, all right, you've had enough.

Penny: Wow, she's being really nice.
Leonard: Yeah, clearly, one of us is dying. Come on, her.

Leonard: Hey, on a completely unrelated note, um, you know, if you'd rather stay at a hotel, we wouldn't be offended.
Beverly Hofstadter: Actually, I've been looking forward to staying with you.
Leonard: Really? It's just, normally, you stay at a hotel.
Beverly Hofstadter: Would you like me to stay at a hotel?
Leonard: No, no, no. I invited you to stay with us.
Beverly Hofstadter: And I accepted, so everyone is happy.
Leonard: Yep. I'm happy, you're happy everyone's happy.

Amy: Are you really not gonna pick up your mother?
Leonard: No. It's fine, she likes to take a cab or a shuttle. That way she can meet people.
Amy: Well, that's kind of nice.
Leonard: Yeah, she always says that a stranger is just a person whose emotional weak point you haven't found yet.
Sheldon: Your mom is the best.

Sheldon: Leonard, when are you leaving to pick your mother up from the airport?
Leonard: Uh, well, let's see, her plane gets in at 3:00, figure half hour to get her luggage, so never.

Leonard: Can't believe it. Sheldon loves telling on people when they break the rules.
Penny: Yeah, well, maybe he's changed.
Leonard: He hasn't changed. Last week, when the vending machine gave me two bags of chips, he called my mom.
Penny: Well, that didn't ruin your life.
Leonard: Well, it ruined my day. I had to talk to my mom, who, by the way, is-is polyamorous now, so that's fun to think about.

Leonard: No, no, I agree with Bernadette. If Pemberton cheated, maybe he shouldn't have a career in the first place. There's plenty of people that didn't plagiarize.
Penny: And a few of us who did, but it's only 'cause The Scarlet Letter was so boring.
Leonard: Aw, I love The Scarlet Letter. That's where I got my taste for bad girls.

Penny: Let's celebrate. What do you want to do?
Leonard: Oh, please don't make me decide another thing.
Penny: Hey, you want to go to SoulCycle with me?
Leonard: Give me a minute, I'll think of something.

Leonard: Well, I-I didn't quit. I said I was going to. I walked out the door and started crying. You know, "Oh, my, God, oh, my God, oh, my God, what'd I do?" And then he called me back in.
Penny: Then he changed his mind?
Leonard: He did not.
Penny: I'm really confused about how to react to this story.
Leonard: President Siebert didn't want to lose me. Even though they couldn't make me a lead investigator on a plasma team, there was an opening for a co-lead on a photon entanglement team. How cool is that?
Penny: You're gonna have to tell me.
Leonard: It's really cool.
Penny: Yay! Oh, I am so happy for you.
Leonard: I almost got what I wanted, and it never would have happened if you hadn't almost believed in me.

Sheldon: Leonard? Um, I have been agonizing over whether or not to say something to you.
Leonard: Aw. Let me help. Don't.

Leonard: Don't take this the wrong way, but that was even more exciting than the sex.
Penny: Don't take this the wrong way, but yes, it was.

Leonard: Yeah, we don't have to.
Penny: No! I like it. Let's go.
Leonard: Oh, o-okay. And then after that, we're gonna watch Star Trek: Discovery.
Penny: All right. Well, just a warning, I might be on my phone for most of it.
Leonard: That's fine. Wait, you mean just the Star Trek- Actually, I don't care.

Penny: I mean, come on, when was the last time you did something totally selfish without worrying about what anyone else wanted?
Leonard: Uh, according to my mother, I took my sweet time being born.
Penny: How is that selfish?
Leonard: Apparently, she had dinner reservations.

Leonard: I think I would've been okay if we weren't sitting so close.
Penny: Well, then, why did we sit so close?
Leonard: Sheldon said, "Are these seats good for everyone?" What was I supposed to do, say no, like a maniac?