Continuity mistake: When Rachel finds out that Ross and Julie are getting a cat, watch Rachel's neck. When she says "together?" she's not wearing a necklace; cut to Ross and Julie for a fraction of a second, then when it cuts back to Rachel saying "both of you?" she's suddenly wearing a necklace. It then disappears again when she says "isn't that just lovely?" hanging off the side of the tray she's holding. (00:05:15)
Continuity mistake: In the scene where Ellen goes to Susan's room after Richard makes a pass at her, she has her jacket in her hand when she enters the room. When Ellen leaves the room hurriedly, she leaves without her jacket, but when she is in the hallway about to go back to Richard's room, she has her jacket in her hand.