The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Chandler is playing with the toy in his office, his right hand moves between shots. (00:09:35)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: At the start of the episode, Chandler is holding onto a menu with his right hand. In the next shot, it is gone. (00:00:10)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: Just after Marcel switches the TV to "SAP," Joey comes back and tells Chandler about Ursula and how she gave him extra food. Chandler is holding a bottle of water, and before the camera cuts to Joey it is open, but when he is talking it is capped, and finally when Chandler says "Score," the bottle is open again. (00:07:05)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Chandler tries to fire Nina, he holds his left hand to his face. In the next shot he is holding his right hand up. (00:10:20)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Ross, Carol and Susan are watching the birth video, Ross has his hand on the fake baby's head. In the next shot his hand is on its shoulder. (00:15:50)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Ross says he's going to be a father, Chandler drinks from his cup. In the next shot the cup is gone. (00:16:55)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: Towards the end, as Joey is leaving Central Perk, Rachel's posture goes from leaving over the back of the sofa with her hands clasped to standing up with her hands on the back of the sofa. (00:18:15)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Rachel says about the name being the same in Spanish and English, the way she holds her chopsticks changes between angles. (00:06:10)
The One with Two Parts: Part 1 - S1-E16
Continuity mistake: When Chandler is saying how cute Nina is, Rachel has her hand in the bag of Chinese food. When the camera cuts, the hand is gone. (00:05:55)
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.