when talking about a building., at or in is fairly interchangeable. When talking about a company, generally at, though for can also work. When talking about a profession or trade, "in" for a white collar profession broadly; "as" for a specific job or for a trade, broadly. When regarding a project, "on." When approaching a task, and trying to get some understanding and mastery, "at."
I'm working at understanding our new software. I'm working on the Jones account. I'm working in finance. I'm working as an assistant to the head accountant. I'm working at Bank of America. I'm working in the accounting division. I'm working for Ms. Skansky, my boss; we work at [or in] the main branch at 1st Street and 3rd Ave.
I'm not sure this is invariant, but I have not thought up a violation of it, yet. I'm sure someone will help. ; )
I'm not quite sure when to use "op" "aan" "in" in these situations. For example, I would have assumed it was working "in" the shoe department (as you're literally inside it), or at least "at" the shoe department (aan/om as it "zit aan/om de tafel?"). How do I decide which to use?
It is sometimes not a matter of deciding which to use, but a matter of memorizing which preposition goes with which verb for a specific meaning. http://dictionnaire.reverso.net/neerlandais-francais/afdeling http://dictionnaire.reverso.net/neerlandais-francais/op http://dictionnaire.reverso.net/francais-anglais/a
op can mean à which means "in", "at" (or "to" but not in this context)
Who (or what) is al bundy? A seller of shoes where you come from?
Additionally, you don't really work for a department in this sense. In the shopping sense, a department is a physical segment of a larger store. You can work for the store, in the department. The kind of department you work for is an organization of its own, such as the Department of Labor.
The shoe department doesn’t even sound like English to me. I have never seen a sign for a shoe department. I have seen footwear department since there are all types of footwear to be purchased, not just shoes. Within a footwear department there could be a shoe section. Not that it matters how English works since this is a Dutch course, however I keep losing hearts for translating sentences in a more natural way! I suppose trying to work out what Duo will accept is part of the game.