The One With the Male Nanny - S9-E6
Continuity mistake: When Ross says, "Not knowing when to shut up, that's my thing," the amount of pizza he has eaten changes between shots. (00:21:50)
The One With the Male Nanny - S9-E6
Continuity mistake: Towards the end, during a scene at Ross and Rachel's, Sandy picks up two puppets and puts them on each hand. He starts pulling the blue one onto his left hand, but when the angle changes there's a yellow one on his left hand, and a blue one on his right. It cuts to Ross, then when we go back to Sandy they've changed hands again. (00:24:30)
The One With the Male Nanny - S9-E6
Continuity mistake: When Ross walks in on Sandy and Joey playing the recorders, Joey puts his recorder down on the table in front of him, when Ross storms out of the room, the recorder is in a totally different position and also on the far end of the table. (00:24:55)
The One With the Male Nanny - S9-E6
Continuity mistake: When Ross storms into the kitchen, exasperated by Sandy, he is immediately followed by Rachel - but she had just been holding Emma, and there wasn't enough time for her to have given Emma to Sandy before storming into the kitchen. (00:25:00)
The One With the Male Nanny - S9-E6
Continuity mistake: In The One With the Male Nanny in series nine, near the end of the episode Ross gets a beer when he is argung with Rachel as to whether they should fire him. During shots, the label on the bottle moves round. (00:25:05)
The One With the Male Nanny - S9-E6
Continuity mistake: The hallway outside Ross' new apartment (series 6 onwards) always changes. Sometimes, the apartment is at the end of a dead-end corridor, and there is a plant outside, covering up the wall; sometimes you can go past the apartment and turn left or right; or, as in this episode, you can only turn right immediately after you have passed the apartment. (00:26:00)
The One With the Male Nanny - S9-E6
Continuity mistake: When Mike and Phoebe are at Central Perk, Mike pulls his apartment key out of his pocket and he's holding the head of the key with the shank side up, but next shot he's holding the shank with the head side up.
The One With the Male Nanny - S9-E6
Continuity mistake: When Phoebe is trying to explain to David that she really cares about Mike the door behind David is closed, but when Mike walks in that door is wide open, and it remains open until it's suddenly closed when Mike warns David that if he ever goes to Minsk he'd better watch out.
Answer: Usually by the seventh night of Hanukkah you don't know what to get the other person, and you will probably resort to getting the other person something insignificant. Chandler is basically saying that the pen is a stupid gift.