Sheldon: So your mirth is merely a discharge of nervous energy with no semantic content at all?
Penny: My mirth. Classic.
Sheldon: Is there a station coming up where I can board your giggling train of thought?
Penny: It's not a big deal, Sheldon. It's just, ever since Leonard's been dating Raj's sister, I've had to keep my distance. I don't get to hear all your jibber-jabber.