Leonard: This train thing worked out better than I thought. He's home studying the engineer's manual.
Howard: It's so peaceful without him here. Can I ask you how much that cost?
Leonard: $4,000. Worth every penny.

Sheldon: I've learned some fun facts about New Jersey to help you make small talk. Would you like to know the state bird or the murder rate? They're both shocking.
Amy: Actually, I want to hear about you. How are things at home?
Sheldon: Well, I'm a lot less likely to see an Eastern Goldfinch or be murdered, I'll tell you that.

Amy: Well, I'm really happy for you.
Sheldon: Oh, no. It's not just me. No, the railway is four hours from the nearest airport, and guess who gets to drive me.
Amy: I give up.
Sheldon: You!
Amy: No. I really give up.

Sheldon: You'll never believe it. Leonard gave me the most incredible gift, a trip to a historic railway, and I get to operate an actual locomotive.
Amy: Wow. He finally used it. What'd you do?
Sheldon: No idea. All I know is, I'm going to be working on the railroad all the live long day.

Bernadette: For Howie's occupation, should I include that he was an astronaut?
Amy: Well, he mentioned it in his mother's eulogy, so why not?

Sheldon: Oh, that was my sixth trip to the bathroom. As long as that's not a urinary tract infection, that's a personal best.

Sheldon: Gentlemen, we need to stop immediately.
Howard: What's wrong?
Sheldon: I am looking at the math, and I think we can make the device between eight and ten percent smaller.
Leonard: That's great, but the Air Force approved the specs. We're good to go.
Howard: Yeah, it doesn't need to be smaller.
Sheldon: Shame on you. Where would we be if poodle breeders had that attitude? I'll tell you. We would have the standard and the miniature poodle, but no toy or teacup. Which by the way, is not an officially recognized breed, but that's just poodle politics.
Leonard: Can we please stop talking about poodles?
Sheldon: Fine. Candy bars. Now, do you enjoy a fun size? I know you do.

Emily: You know, the same thing happened to me. After I broke up with Raj, I met Gary, who's just amazing.
Howard: Sorry, is that "Gary" with one R or two?
Raj: Would you stop writing?!

Penny: Look, we got really angry at each other, and you just got caught in the middle of it.
Leonard: And sorry about the suitcase.
Sheldon: Yeah, well, you should be. Your socks were still in it. I had to throw it away.

Leonard: We owe you an apology.
Sheldon: Oh, it's fine. You needed a suitcase, I wasn't home, you borrowed a suitcase.
Leonard: That was six years ago. I'm talking about tonight.
Sheldon: Oh, well, I thought we were going in order.

Raj: Okay, maybe we should just end this.
Howard: Wait, hang on. I just want to point out to everyone here, this is a man who is going to great lengths to better himself. Even at the risk of being humiliated. And I, for one, think that's very brave.
Raj: Thank you, Howard.
Emily: Honestly, I'm surprised you two didn't wind up together.
Howard: Well, like you gals, I had to suffer through him to find Bernadette.

Howard: (Interpreting for Emily #1) "I thought you were great, but, oh, my God, you were so dominated by your parents."
Emily #2: Oh, yeah, and that used to drive me nuts. He's kind of a mama's boy.
Claire: Kind of?!
Raj: Whoa, okay! That's enough. (To Howard) Write down "loving son."

Raj: Oh, I know, why don't we get started on clearing out the baby's room?
Bernadette: Isn't it a little early for that?
Raj: You have to get to it eventually.
Bernadette: Oh, there's so much junk in there, it's embarrassing.
Raj: How can you be embarrassed around me? I'm gonna be in the room with you when you give birth.
Bernadette: I don't think you are.
Raj: You didn't think I was gonna be in your kitchen this morning, yet here I am.

Howard: I'll make you a deal. Thirty years from now, if you're still single and things don't work out with me and Bernadette you and I can give it a go.
Raj: I appreciate the offer, but if things don't work out with you two, I'm swooping in on her like a vulture.
Howard: Too late. Stuart called dibs.

Raj: So, what should we do today?
Bernadette: Oh, I appreciate it, but you don't have to spend your day off with me.
Raj: Well, I don't mind. Oh, you want go to the mall and look at baby stuff?
Bernadette: Not really.
Raj: Oh, come on, we could share a pretzel and get sideways glances from racist old ladies.
Bernadette: I get enough of that when I take Howard to my grandmother's for Christmas.