Bernadette: I don't know what you think you're doing, but this is a very difficult time for my husband. We're eating the last food his mother ever made. And you are going to throw it at each other like children? Whatever it is you're fighting about, put it aside, go back in there, be a good friend to Howard, or there's no dessert for either of you.

Howard: I'm sorry I didn't take you to the airport. I just want you to know I'll never forgive myself for being so selfish. And I promise to keep you close for the rest of my life.
Bernadette: Oh, no, that thing's gonna end up in my bedroom.

Bernadette: (Shouting from the bathroom) How many times do I have to tell you to replace the toilet paper when it's empty?
Howard: I'm in the middle of something.
Bernadette: So am I!

Bernadette: Gosh, Amy. I'm sensing a little hostility. Is it maybe because like Sheldon's work, your sex life is also theoretical?

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Penny: Wow, it looks really pretty in here.
Stuart: Yeah, turns out half a dozen Menorahs really sets a mood.

Howard: All Ma's food is going to be ruined.
Bernadette: Why don't we take it home and put it on our freezer?
Raj: You don't want to do that. Refreezing not only removes moisture, but it creates ice crystals in the fibres of the meat that can compromise its taste and texture. What? I saw a teachable moment. I dropped some culinary science.