Character mistake: In the Armchair Theatre story, Billy mentions that the grandma puts a tray of chocolate brownies into the oven. In the next scene the grandma (played by Billy Butler) has a tray of cookies, not brownies.
Character mistake: Tracy supposedly rips Lydia's tongue out to stop her from screaming. The only problem is that the tongue is not needed to produce a scream.
The Wedding - S8-E23
Character mistake: When Roseanne, Darlene, Jackie, Bev, Becky, and Nana Mary are dressing for Darlene's wedding, Nana Mary comments that all of them were pregnant when they married. However, Becky, was not pregnant when she and Mark eloped and they never had children together. Roseanne was not pregnant before marrying Dan. When the series began, Becky was 13 years old and Dan and Roseanne had been married 15 years.
Character mistake: Bessie's last name is misspelled "Higginbottom" on the newspaper Happy shows her.
Break Out the Pampers: Part 2 - S3-E2
Character mistake: Near the end of the episode, when Ms. Rafkin stops by to see the Rush family, Sara greets her by name. Ms. Rafkin (who thinks her looks have changed due to a facelift) asks Sara how she knew it was her. Henry told her by her voice which she accepted as the answer. This wouldn't be a possibility since Sara said hello before Ms. Rafkin spoke.
Character mistake: Lucy Liu-bot says Fry's name normally, but uses an automaton voice for "Can eat more", when she has always used Fry's name as a Text-to-speech type of automaton voice. (00:07:45)
Character mistake: Max enters Brad and Jane's house to find Brad dancing with Santa, Max then calls Brad "Dave." (00:09:18)
Character mistake: Sue White suggests speaking in Portuguese but what she says next is actually Spanish. (The subtitles incorrectly say she is speaking Portuguese). (00:04:00)
Welcome to the Great Beyond - S7-E4
Character mistake: Calvin is cleaning a gas BBQ grill, and they refer to it as a smoker. (00:00:26)
The Kidney's All Right - S3-E9
Character mistake: Arthur wants to donate his kidney to Derek. It is claimed that he must be a match since he has O negative blood, but blood type is not the only thing required for a kidney donor, there are several other factors that could very well disqualify his kidney for Derek.
Character mistake: Jessie's dance moves don't match what the other girls are performing, even though it's a choreographed routine.
Character mistake: Eddie, Spudgun and Dave Hedgehog all appear worried at the fact that the devil takes "virgin's blood." However, it is apparent later in the episode that the 'devil' is in fact Dave Hedgehog's daughter, meaning he isn't a virgin.
Suggested correction: Also, Eddie previously slept with the Third Viscountess of Moldavia when Richie's back alley kidney donation backfired and he collapsed, so he wasn't a virgin either, but reacted as though he was.
Although theoretically correct, bear in mind that neither Eddie or Dave Hedgehog aren't particularly bright, and likely forgot they weren't virgins.
Hedgehog's daughter could have been adopted.
Character mistake: When talking to Will on the phone, Grace misuses the term "pied-à-terre" (which means "apartment" in French) instead of "pas de deux" (a dance for two) while describing the delicate and complex nature of a relationship between two gay men. When Will points out her error, she says she knows what pied-à-terre means because she took Spanish in high school. However, in season 1, episode 20 ("Saving Grace"), Grace correctly and easily used the term pied-à-terre while showing her sample book to a potential client.
Character mistake: When Fiona and Ford are lying on the mattress looking up at the compass on the ceiling, the compass is improperly painted. With west on the left, north would be at the top, not the bottom as depicted.
Character mistake: Mark walks into the house and is surprised to see Cody there, and remarks that he heard he was back. However, just before this, when Mark entered the house, Cody's van - which Mark had to walk by to enter the house - was visible through the open door, so that should have confirmed it for Mark before he saw Cody in person.
Lady Florence Craye Arrives in New York (or, the Once and Future Ex) - S4-E2
Character mistake: Cheesewright is trying to convince the police to raid the charity ball because alcohol is going to be served. The police chief tells him they stay out of private affairs and Cheesewright replies "The law's the law!" Prohibition made illegal the sale and transport of alcohol, but people were still allowed to have it in their homes or private functions. No laws were being broken. (00:33:30)
Transformers (Lost episode) - S1-E7
Character mistake: When Donnie turns to the cameraman, Carl, and asks if he liked the film they just made, he responds in a normal American accent. Carl has been established in the series as German with a thick German accent, and the actor playing him, Rob, either forgot to use the accent or just didn't at that moment with them forgetting to change the audio in post. (00:03:55)
Family in Paradise: Part 1 - S4-E25
Character mistake: The hunky male tour guide compliments Cissy on her brown hair when she's an obvious redhead.
German for Beginners and a Crazy Old Man with a Bat - S6-E20
Character mistake: Sheldon says that "entrez vous" is German for "come in." That is actually French.
Suggested correction: He says "eintreten."
I'll See You in Court - S5-E20
Character mistake: Charlene says Rocky was nominated for 9 Oscars, it was actually nominated for 10 but in 9 different categories.