05E19 - The One Where Ross Can't Flirt

First, Ross takes Chandler's natural joking with pizza delivery girl Caitlin for flirting behind Monica's back, and actually tells her just as they celebrate their 10-month anniversary, which starts a discussion on whether flirting by men is innocent, but not by females. Then Ross decides to demonstrate his flirtatious talent, which the others know to be abysmal; even conquering Rachel took him nine years. Meanwhile, Joey brings over Nonnie, his Italian grandmother who doesn't speak any English but was his only relative who always believed in his career, to watch a "Law and Order" episode in which Joey has a small role. Once he realizes his scene has actually been cut out, everyone tries to fool her and thus spare her heartbreak. Phoebe can't return Monica's earrings, a gift from Chandler she wants to wear that evening, because Rachel borrowed and lost them, as usual. Ross's flirting lessons turn out to be of the 'how not to do it' variety, but Rachel takes pity on him.