"My father is next to my mother."
You should use よこ because となり is used for non equals elements Like using となり makes the mother and the father not equals. At the opposite, よこ makes the father and mother equals : you wont use it to say "My mother is next to the table" I am not sure at all but you should look in the way (I learned this rule on this forum Duolingo it is not from me)
I might be wrong, but I don't think that is incorrect. It may sound weird though.
I saw someone else posted a good answer for this on another exercise.
となり is for two SIMILAR objects that are next to each other. For example two houses, two people standing next to each other etc.
よこ is for two DISSIMILAR objects next to each other. For example a person standing next to a house.
A way to memorize this is by the famous Japanese city of よこはま, which I think someone translated to "next to the beach" (despite google translate not recognizing はま... idk I'm not that good at 日本語). The CITY is next to the BEACH, these are DISSIMILAR objects, and therefore the town is called よこはま and not となりはま, if that makes sense :)
However, by this "rule" I was surprised the answer for this exercise isn't using となり, but instead よこ (mom and dad are both humans). Don't know what's up with that, so someone more experienced please fill in :)
I was surprised too, because I was studying Japanese and Just using duoligual to see how much I know. I know you supposed to use となり
I came here to check on that, too. Is one or the other more natural in conversation? Or are they both just as good?
As far as I'm aware both are fine, they just mean slightly different things
父は - speaking of my father, he's next to my mother
父が - it's my father who's next to my mother
so one is generally talking about where yr dad is, the other is sort of specifically pointing him out, or it's focused more on the location and then saying who's there. It's subtle (and I think learning the nuances of は and が is like a life quest)
I don't think it makes a huge difference, although the given translation might be more natural-sounding. They are both correct, though and this structure should be accepted.
The inconsistency between は and が in Duolingo use is driving me insane. I have just completed other 3 sentences in the same exercise structured identically like this one where が was correct and は incorrect in this function, and now all of a sudden it is the other way around?
I get it that sometimes both are valid (with only a slightly different nuance), and sometimes only either of them, but I get the sneaking suspicion that Duolingo doesn't know which either.
the answer uses Kanji in the program, the answer uses hiragana "yori" on this page
横（よこ） means "horizontal" or "side", as a noun. To make it a preposition, you need to include の before it and に after it; の横に（のよこに） functions as a preposition meaning "beside, next to".
Could someone tell me why this is incorrect?
It is in the same basic structuring as a correct answer in another phrase:
The first sentence does say next to what. It translates to "As for my father, my mother exists next to".
Whereas, in the second sentence, the subject is not stated but inferred. It translates to "There is a table in front (of you/us)".
this section seems so confusing for me, it seems like the order and grammer varries a lot for some reason. I have some how managed to make it this far without, apparently, understanding some basic concepts of sentence structure and joiners