Translation:Sometimes she writes articles for a magazine.
Isnt статья singular? I dont understand why that is incorrect. "She sometimes writes an article for the magazine." Sounds correct to me.
писать requires the accusative which is статью. The same is true for plural, but since it is an inanimate noun, plural accusative is the same as plural nominative (статьи).
I might just be an idiot, but it's easy to make the mistake that the noun is supposed to be singular, which is not possible as статью is not available.
Sorry, I don't really understand your question. The verb (пишет) is indeed singular, but that's because of who is writing (она - singular), not because of what she writes. The verb would be the same regardless of whether she writes one article (статью) or many of them (статьи).
In my understanding, "за" would mean she writes articles in exchange for a magazine, whereas "в" means her articles are printed in one.
извиниться, can someone explain why it is "в журнал" instead of "в журнале"?
извиниться (infinitive) → извините (polite or plural imperative)
In any case, as you probably know, some Russian prepositions, most notably в & на take both accusative and prepositional cases depending on the intended meaning. Prepositional is used to indicate location ("inside" for в or "on top of" for на) while accusative - to indicate direction (into/onto).
So, "писать в журнале" (prepositional) would mean that you have a journal/magazine in front of you and are scribbling something inside. On the other hand "писать в журнал" means that the journal/magazine (not a printed issue but the editorial board) is the intended recipient of your writing.
большое спасибо for your extremely helpful reply. I didn't think of writing to the journal (as in the board), that makes so much more sense now.
"за журнал" would mean that the magazine itself was supposed to write those articles but she does it for them instead.
This is confusing as hell. How are we supposed to know that she writes articles rather than an article? By only the choice of 1 correct plural response and the lack of статью ? And what is wrong with : Иногда она пишет статья для журнала? Google Translate and Yandex Translate say there is nothing incorrect about it although it may not be the best choice.