Leonard: Again, I'm sorry. I shouldn't have kept it a secret.
Penny: Well, I have a secret I've been keeping from you, too.
Leonard: Is it a secret bank account? Because that would be awesome.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Bernadette: He's just trying to be supportive.
Howard: Just supportive. Not over-the-top in any way?
Bernadette: No.
Raj: Hello. (Raj walks in with a gigantic teddy bear)
Bernadette: You saw him carrying that?
Howard: Astronauts saw him carrying that.

Penny: I'll see if it's available.
Amy: You know, if that study's real, Leonard might come back smarter than you.
Sheldon: Are you trying to manipulate me?
Amy: Yes.
Sheldon: Well done, it worked, we're going.
Amy: Yay!

Raj: Of course. I'll give you guys some space. Let me just get this out of your way. (Raj fumbles around trying to move the gigantic teddy bear. He knocks over various objects in Howard & Bernadette's living room)
Howard: You need some help?
Raj: No, I got it.
Bernadette: Raj, Raj, wait.
Raj: Please, Bernadette. Let me leave with my dignity. (Raj falls over the teddy bear as he tries to move it out the door)