Corrected entry: Marge is reminding Lisa of the differences between the UK and the USA before she goes to visit Hugh's family in England. Obviously the steak-and-kidney pie remark is a joke, but she says, "Remember, a mile is called a kilometer..." No it isn't. The metric system is used in mainland Europe - miles over here are still miles.
And Maggie Makes Three - S6-E13
Corrected entry: When Marge tells Homer that a new baby is on the way (Maggie obviously) look in the background and you can see a photo of Maggie already there.
Corrected entry: During the opening dream sequence on the "Planet of the Donuts", we get our first glimpse of the monster donut that will eat Homer when his shadow looms over Homer. In this shot the shadow is of a "regular" donut, i.e., one with a hole. In the next shot we see that the monster's hole area has teeth and is filled in with black; in other words, its hole is a regular mouth. As such it could not have had light shining through it to make the donut hole in his shadow.
Correction: It is a dream. Dreams don't make any sense and are not bound by any laws of reality. The donut could have grown teeth and a mouth between shots.
Skinner's Sense of Snow - S12-E8
Corrected entry: When Skinner is doing lines on the board, Bart shows how his wrist sounds after years of doing lines. However, he rotates his left hand, and in every other episode where Bart writes anything we see he is right handed.
Correction: Bart is (and has always been) left-handed. Check out which hand he writes with in the opening credits. This is because Matt Groening himself is left-handed - it's just that sometimes the animators forget, so in some episodes Bart is shown to be writing with his right hand.
Corrected entry: There were five judges at Homer's court martial, however, four of them walk away, so there should be one left, but all five chairs are empty.
Correction: There is no requirement that they show every judge walking off. Since the judges who speak are shown in mid-shots that do not allow us to see all of them at once, there is no reason to think the 5th judge could not have walked off quietly without speaking while we were watching one of the others.
Dude, Where's My Ranch? - S14-E18
Corrected entry: This is a minor mistake, but why does Luke say he needs help "hanging up these signs" when they have a stake on the end to impale them into the ground? If he had said "put up" then OK, but he said "hang," so this is a mistake because there is no way to hang them up like a hook or something.
Correction: It is just a simple expression that does not necessarily mean what it says, just like "kick your butt" could involve no kicking.
Corrected entry: When Marge goes to the ballet with Ruth Powers, she has a purple coat with fur around the top. They go to the ballet, and when they come out Marge hasn't got the coat.
Correction: She forgot it at the ballet - character mistake.
Corrected entry: The oil stain on the Simpsons driveway changes from being there to not being there depending on the episode.
Correction: Seeing as this is between episodes, something could have happened to get rid of the stain and cause it to be there. For example, by one episode it could have been cleaned and by another the car could have leaked some oil. If that happened often, then it was probably done for humour.
Tree House of Horror II: A Simpsons Halloween - S3-E7
Corrected entry: Mr. Burns and Smithers put Homer in the bag. They weren't carrying a bag when they got to the cemetery. (00:17:20 - 00:18:10)
Tree House of Horror II: A Simpsons Halloween - S3-E7
Corrected entry: At the end of Part 1, the crowd carrying Flanders jumps from being on his front lawn to the middle of the street. (00:08:30)
Correction: No they don't, they are on the pavement in every shot.
Tree House of Horror II: A Simpsons Halloween - S3-E7
Corrected entry: When the family (except Marge) starts eating candy, their costumes are suddenly off, when they never had time to take them off. (00:01:25 - 00:02:15)
Tree House of Horror II: A Simpsons Halloween - S3-E7
Corrected entry: When Homer shuts the door after his candy gets stolen, we only hear eggs being thrown at the door. In the next shot, the pumpkin beside the door appears to be broken. (00:01:20)
Correction: They presumably kicked it or stood on it which wouldn't necessarily be a loud enough noise for us to hear from inside.
Lisa's Pony - S3-E8
Corrected entry: Homer takes a drink of his beer, but his mouth doesn't open. (00:14:25)
Correction: His mouth may only be slightly open, and you don't need to fully open your mouth to drink. It is possible to drink with your mouth only slightly open.
Lisa's Pony - S3-E8
Corrected entry: The kitchen appears to be very different after Marge finds out Homer bought a horse. (00:12:10 - 00:13:00)
Correction: The kitchen does not at all look different.
Lisa's Pony - S3-E8
Corrected entry: When Lisa calls Homer at the power plant, the same footage of him sleeping and waking up in the beginning is used. (00:18:55)
Correction: There is nothing contradicting continuity by reusing this shot, so this isn't really a mistake.
$pringfield (or How I Learned to Stop Worrying and Love Legalized Gambling) - S5-E10
Corrected entry: When Mr. Burns is laughing in church it has a purple interior instead of its usual orange.
Correction: Looking at the shot inside the church there is nothing to indicate that this is the local church that most the townspeople go to. Everything about the church is different from the local church including the walls (which are blue not purple) and the glass paned windows. Being also there is no familiar faces in the church its more likely that this is a different church.
Tree House of Horror II: A Simpsons Halloween - S3-E7
Corrected entry: While Bart is watching TV, Homer comes home, and Bart is holding a bottle. He never had it when he came into the living room. (00:12:15 - 00:13:35)
Corrected entry: When Homer gets stuck in the water slide, a few kids are sent down to dislodge him, and they get stuck too. However, when the section of pipe containing him is removed later, the kids are nowhere to be seen.
Correction: They were able to pull the kids back up the slide, since they weren't wedged in the pipe like Homer was.
Moaning Lisa - S1-E6
Corrected entry: During dodgeball, either Sheri or Teri is one of the kids throwing balls at Lisa. Only problem is, she is in Bart's class, not Lisa's.
Correction: It is quite possible that they have dodgeball at the same time.
Strong Arms of the Ma - S14-E9
Corrected entry: Homer has to play Tetris to get all of the garage-sale items to fit into the station wagon, and even then he can't fit himself in. Yet when they arrive back at the house, everyone has a comfortable amount of room.
Correction: This is a joke -- showing how Tetris is like filling a car with objects.
Correction: This is clearly a mistake on Marge's part, as she is unfamiliar with European life and makes things up based on expressions she vaguely remember hearing about. And isn't it possible, since this episode takes place in the future, that the UK has joined the rest of Europe and switched to the metric system?
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