In season 6 of Friends, Joey pretends to own a Porsche, Ross and Monica debut their dance-routine from college, Phoebe and Rachel take a run through Central Park, and Ross starts dating one of his students, Elizabeth.

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The show's sixth season first aired in 1999 and, like the others, has numerous continuity errors that only eagle-eyed viewers will spot. Before the reunion, which is reported to be filming in the later summer, let's take a look back at season six and see how many of these gaffes you spotted the first time around.

Phoebe's Run

In episode 7, 'The One Where Phoebe Runs,' Rachel is embarrassed to run with Phoebe in Central Park after she learns of the embarrassing way that Phoebe runs. Rachel resorts to lying about her ankle so she can secretly go running by herself.

When Phoebe learns that Rachel lied, she ambushes her in Central Park, and we can see an older man in a grey sweater running past Rachel. But then in the very next shot, the same man runs past Phoebe and Rachel again.

Rachel's Trifle

Rachel shows Joey and Ross her trifle in Friends

In episode 9, 'The One Where Ross Got High,' Rachel accidentally mixes up two recipes while making a dessert for Monica's Thanksgiving dinner. She makes half a trifle with cream and jam and half a shepherd's pie with meat and onions.

While the gang tries to dispose of the dessert secretly, they each go to separate rooms. However, although we can still see Joey enjoying the dessert, the amount on his plate gets bigger and smaller between shots.

Visible Crew Part 1

Janine at Monica's apartment in Friends

In episode 10, 'The One With Routine,' Joey's new dancer roommate, Janine, invites Ross and Monica to a taping of 'Dick Clark's New Year's Rockin Eve,' where they show off their old routine from high school.

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When the gang is in Central Perk, Janine invites Monica and Ross to the taping, gets her coffee to go, and then gets up to leave, but a camera and a crew member can be seen on the far left as she stands up.

Janine's Escape

Janine and Monica fighting in Friends

In episode 11, 'The One With The Apothecary Table,' Janine expresses her dislike for Chandler and Monica, saying that Chandler is very "blah" and that Monica "is very loud for such a small person." Joey tries to make Janine like them by going out with them again.

At the end of the episode, Janine pretends to make up with Monica, but then Monica overhears Janine insulting her under her breath and hits her with a garbage bag. In the next shot Janine starts running away, but in the next shot she is standing still and then starts running away again.

Jill's Arms

In episode 13, 'The One With Rachel's Sister,' Rachel accidentally convinces her sister Jill (played by Reese Witherspoon) to go out with Ross. When Rachel tries to talk her out of it, Jill says that dating a geek will be something new and that's why she wants to try it.

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As she says this, her arms are crossed against her stomach, but in the next scene, her hands are crossed on her knees.

Wet Paper Towels

In episode 18, 'The One Where Ross Dates a Student,' Phoebe and Rachel argue over who will stay at Monica's apartment and who will stay at Joey's. The two move back and forth, but eventually, Rachel decides to stay with Joey, where they throw wet paper towels.

Monica ends up driving Phoebe crazy with her obsessive cleanliness and Phoebe goes across the hall to try and switch with Rachel. As the two are talking, the wet paper towels on Joey's television cabinet keep changing positions between shots.

Rachel's Coat

In episode 19, 'The One With Joey's Fridge,' Joey tries to convince Rachel to pay $400 for a new fridge. She laughs and says that she's only staying at Joey's apartment until her apartment gets fixed and she leaves for work.

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Just before she leaves, Rachel can be seen putting her left arm into her coat to put it on, but in the very next scene, the coat is draped over her arm.

Rachel's Coke

In episode 22, 'The One Where Paul's The Man,' Ross and Elizabeth go up to Elizabeth's cabin that Rachel and Elizabeth's father, Paul, also happens to be going to. Ross tries to hide from Paul when he arrives and when Rachel finds Ross, she too attempts to hide him from Elizabeth's father.

One distraction she uses is to ask Paul to get her coke with ice, and when Paul gives it to her, she has it in her right hand. In the next shot it switches to her left, then back to her right hand in the following shot.

Chandler's Credit Card

In episode 23, 'The One With The Ring,' Chandler gives Joey his credit card so he can buy Monica an engagement ring. When Ross and Joey are in Central Perk, Joey takes Chandler's credit card out to pay for his and Ross's coffees.

When we see Chandler get his card off of Joey later on in the episode, it is an American Express card, whereas the card Joey had earlier was a MasterCard.

Chandler's Champagne

In episode 24, 'The One With The Proposal: Part 1,' Chandler and Monica go out to dinner so that Chandler can propose and they order champagne, but little does Chandler know that they will bump into Monica's ex-boyfriend, Richard.

When the waiter arrives, he brings two champagne glasses, one that is already full, and he fills up the second glass. However, in the next shot, the waiter is filling up the same glass, but the other glass is now empty.

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