The One With The Fake Party - S4-E16
Visible crew/equipment: While Rachel's explaining how to play 'spin the bottle' the bottle she spins points to Gunther, and in the shot facing Gunther we can see the end of the set wall, at the right side of the screen.
The One With The Fake Party - S4-E16
Visible crew/equipment: After Ross finds out that Monica told Emily about how he used to play dress up and host make-believe tea parties, when Monica stands up we can see set lighting near the bathroom, at the top of the screen.
The One With The Fake Party - S4-E16
Continuity mistake: After Rachel spins the bottle and it points to Joshua, when she crawls over to him on her hands and knees the bottle's in front of her knees, but in the next shot facing Joshua the bottle is to her side, near her feet.
The One With The Fake Party - S4-E16
Continuity mistake: When Joey takes the steaks out of the freezer, Phoebe's holding a napkin up by her face with her left hand while her right hand is down and empty, but in the next shot it's her right hand that's up with a napkin.
The One With The Fake Party - S4-E16
Continuity mistake: When Emily says that she'll go first at spinning the bottle we see the door behind Ross is wide open, but after Emily spins the bottle that door is closed, yet it's wide open again during the game and then closed.
The One With The Fake Party - S4-E16
Continuity mistake: While Joey spins the bottle and it keeps pointing to Emily, in the shots facing Ross the door behind him goes back and forth from being either closed or wide open, depending on the angle of the shot.
The One With The Fake Party - S4-E16
Continuity mistake: After Rachel spins the bottle and it points to Joshua, when she crawls toward him on her hands and knees the bottle is in front of her knees in the shots facing her, but in the shot facing Joshua the bottle is at her side, near her foot.
The One With The Fake Party - S4-E16
Factual error: Phoebe says in the show that she's three months pregnant. Not only is she way too big for that, but the fetus also kicks for the first time. Women don't feel fetal movement until 16 weeks at the earliest, and for a first pregnancy it may not be until 25 weeks or so.
Suggested correction: Phoebe's size could partially be explained in that she was carrying triplets, though Lisa Kudrow was pregnant in real life, and was further along than her character. Her pregnancy had to be written into the show and the gestation timelines did not match up. Phoebe feeling "movement" could just be her imagination, as her character is supposedly somewhat psychic and often perceives things that are not necessarily discernible to others or isn't even real.
The One With The Free Porn - S4-E17
Other mistake: 10:50pm boarding and departure, but it is broad daylight outside. (00:09:25)
The One With The Free Porn - S4-E17
Continuity mistake: When Joey is asking Ross why he told Emily that he loves her, Joey's bottle of juice is right in front of him. In the next shot of Joey, there's two bottles - Monica's Diet Snapple and Joey's juice, and in the next shot it's back to one again. Monica's drink appears and disappears throughout the scene. (00:11:25)
The One With The Free Porn - S4-E17
Visible crew/equipment: After Emily says thank you to Ross and leaves, when it cuts to Chandler and Joey's apartment Rachel puts a tea bag in her mug, and in the wideshot as she says, "He told me," the camera can be seen at the left side of the screen.
The One With The Free Porn - S4-E17
Visible crew/equipment: After Joey asks Ross to buy him a Toblerone just as Ross heads out to the airport, when it cuts to the shot of Rachel and Phoebe walking into the apartment, the camera can be seen at the right side of the screen.
The One With The Free Porn - S4-E17
Continuity mistake: Near the end, when Emily walks into the house, the TV should be on with the porn. But instead, it's turned off.
The One With The Free Porn - S4-E17
Continuity mistake: In the scene where Phoebe tells the gang about her "Relaxitaxi" idea the position of Chandler's left arm changes between shots. In the frontal shots it's lying the back of the chair and in the shots from behind it's wrapped around Monica's shoulder.
The One With The Free Porn - S4-E17
Factual error: We know that Phoebe is three months pregnant, because it's the day after the party where she told Joey that she was three months along. But the ultrasound shows three little lumps that in no way resemble a three-month fetus. An actual three-month fetus is the size of a jellybean.
The One With The Free Porn - S4-E17
Other mistake: The new York to London time sequence makes no sense. The friends are all wearing the same clothes throughout most of the episode. Emily flies from London back to New York and Ross flies to London, most trans Atlantic flights are overnight. It's very unrealistic that Ross got to London in the same day, and she flew back so quickly after getting back to London' even though Ross had only just said goodbye to her. The characters' clothes show this is all taking place in the same day.
The One With The Free Porn - S4-E17
Continuity mistake: In the beginning when Rachel says "Do we really have to watch this while we eat." From the front view Rachel's arms are crossed and then from the back their are by her side and back with no time to turn.
The One With Rachel's New Dress - S4-E18
Continuity mistake: When Monica tells Rachel what she is cooking, and Rachel says "I really get crabby when I cook" she crosses her arms and in a flash they are on the counter again. (00:06:00)
The One With Rachel's New Dress - S4-E18
Continuity mistake: When Rachel shoos the birds into the hall, the chicken turns around and heads away from the guys' door, however when Joey opens the door the chicken is right outside the door. (00:10:15)
The One With Rachel's New Dress - S4-E18
Continuity mistake: In The One With Rachel's New Dress, she's in her underwear on the sofa when Joshua comes in. In wide shots focusing on Joshua she's quite laid back, but in close shots of her she's sitting more upright. Worse than that, her legs are crossed, but uncross in the shot of his parents coming in, only to re-cross in the next shot when she gasps. (00:14:35)