The One With All The Cheesecakes - S7-E11
Continuity mistake: When Ross and Monica are at the wedding reception talking to the other guests at their table, a lady wearing a red scarf is standing behind them with her back turned. Throughout the scene the red scarf keeps changing position very quickly - in one shot it's slid down one shoulder, then back up in the next and then slid down again. At the end of the scene it's off her back entirely and she has just slung it over her arms. (00:12:15 - 00:13:15)
The One With All The Cheesecakes - S7-E11
Continuity mistake: Chandler walks into his apartment to find Rachel eating cheesecake without him. As the door is shutting, the pen on the Magnadoodle is hanging loose; it can be heard hitting the door when Chandler is closing it. The next shot shows Rachel stop eating, and when we next see Chandler, the door is closed and the pen is in its holder. (00:15:50)
The One With All The Cheesecakes - S7-E11
Continuity mistake: Just after Rachel has tried to whistle and just blew out crumbs, she picks up the fork with her left hand and places it to the left of the cake on the kitchen counter. In the next shot just before Chandler picks up the cake the fork is back on the right side of the cake near her right hand. (00:16:05)
The One With All The Cheesecakes - S7-E11
Continuity mistake: In the scene when Phoebe says goodbye to David, you can see Phoebe's long hair on her back. The scene goes back and forth between Phoebe and David or Phoebe and Joey (after David leaves). Each time the amount of hair on Phoebe's back changes. Sometimes it is a thin bit of hair, other times a large chunk (while the rest of her hair is framing her face in front). (00:19:10)
The One With All The Cheesecakes - S7-E11
Continuity mistake: When Rachel and Chandler are out in the hall eating cheesecake off the floor, Chandler's piece is much closer to Rachel's piece than in the previous scene when Rachel slapped it out of Chandler's hand closer to the apartment doorway.
The One Where They're Up All Night - S7-E12
Continuity mistake: There is a long shot of Rachel and another person sitting on the sofa and Rachel's wine glass is almost empty. She then goes over to the the counter to fill it up. However, before she starts to fill it, a significant quantity of wine can be seen in the glass. (00:07:35)
The One Where Rosita Dies - S7-E13
Continuity mistake: In this episode we seemingly understand why Ross and Monica's parents favor Ross. In one scene at Monica's apartment Ross says that it is because their parents thought Judy was barren. This would make sense except that in TOW Rachel's Book, Jack and Judy tell Monica and Chandler that they had to get married because Judy was pregnant. Judy was using a diaphragm as birth control and Jack's dog ate it. It doesn't make sense that Judy would use a diaphragm if she thought she was barren. This was not news to Monica since she said she had heard the story about the dog eating her mother's diaphragm at her 5th grade Halloween party. (00:04:15)
The One Where Rosita Dies - S7-E13
Continuity mistake: When Chandler and Rachel figure out that the chairs were switched they both head over to Joey's apartment. When they enter the apartment, the new black chair can be seen with tags attached to the top and left side. When the scene cuts to Joey sitting down the tags are all missing from the chair. (00:20:05)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: As Monica is giving her speech while drunk, at one point her hands go from her sides to gripping each other between shots. (00:00:10)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: In one of Monica's flashbacks, her hands move between shots with no time to do so. (00:10:50)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: In the shot of Tag giving Rachel a scooter, her shirt is fine. The next shot of Rachel, she has a bow from the present on her shirt. The next shot is of Chandler, then next shot of Rachel the bow is gone again. (00:11:55 - 00:12:25)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: When Monica is at the party and she is drunk, there is one point when she is sitting down on a chair with Chandler on her right. Chandler is holding her left hand (which has a snack in it), but when it cuts to a front view of Monica, suddenly both her hands are on her lap. (00:13:45)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: Rachel's birthday has always been in May, not February/March. (00:16:00)
The One Where They All Turn Thirty - S7-E14
Continuity mistake: Rachel is said to be the youngest in the group as they reminisce about their 30th birthdays, however this episode reveals that almost all of the characters ages have been inconsistent throughout the series. In Season 1, Joey is said to be 25. In Season 2, he says he is 28. In S7 E1, he says he is 31. In Season 1, Monica is said to be 26. In Season 7, she should therefore be at least 32. Rachel graduated high school with Monica, so she should also be about 32 in S7, not just turning 30. She would have been 26 in S1. But, in Season 4, she refers to herself as a "28-year-old cheerleader". Based on Season 1, Joey should actually be the youngest member of the group, not Rachel.
The One Where They All Turn Thirty - S7-E14
Continuity mistake: In The One Where They All Turn Thirty, it is Rachel's birthday. They show flashbacks of all the other Friends' thirtieth birthdays despite Monica's birthday supposedly being months after Rachel's. Plus, earlier on in the show Joey was 25 when Monica was 26, and since Monica and Rachel were in the same grade Joey should actually be a year younger than them, not a year older.
The One With Joey's New Brain - S7-E15
Continuity mistake: When Joey is talking to the woman whose brain he receives, as the shot changes she is holding a glass, then a cigarette then a glass again, with no time to change objects, let alone anywhere to put the other. (00:06:05)
The One With Joey's New Brain - S7-E15
Continuity mistake: When Chandler, Ross and Monica are in Central Perk discussing playing bagpipes, and Ross says, "Decide whatever you want," he is gesturing with his right hand up and with an open book in his left hand. When the camera angle changes, the book is closed and is now in his right hand. (00:15:30)
The One With Joey's New Brain - S7-E15
Continuity mistake: When Rachel appears when Joey has the actor in his appartment, the door is closed. When she goes to get Monica, the door is open. (00:21:30)
The One With The Truth About London - S7-E16
Continuity mistake: At the beginning when Chandler is talking about two reasons to pick a minister, he counts them using his left hand. However, in the wide shot straight afterward his right hand has two fingers up and his left hand is in his lap. (00:02:00)
The One With The Truth About London - S7-E16
Continuity mistake: In the opening credits, Monica and Chandler are talking about which minister to use. Chandler's feet are crossed and on the table; at first his left leg is over his right, then in another shot his right leg is over his left. (00:02:45)
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.