Friends - Season 5 Episode 11 The One with All the Resolutions I'll be there for you.
Overview: With the New Year, the friends make New Year's resolutions. Ross resolves to try a new thing every day. Chandler resolves to not make fun of his friends for a week. Joey resolves to learn how to play the guitar, with Phoebe as his teacher. Rachel resolves to give up gossiping. Chandler nearly goes insane holding it all in. Ross is stuck in a sticky situation at his date's apartment, in constricting and hot leather pants. Rachel discovers a big secret (Monica and Chandler) that threatens to spoil her resolution.