"Her document is a long discussion."
Translation:Su documento es una larga discusión.
Some adjectives (generally: size & beauty) comes before the noun. Actually, the place of the adjective depends on whether one sees it as subjective or objective. When it's before the noun, it's subjective and when it's after the noun, it's objective. Since size and duration are subjective (i.e. the discussion can be long for you, but short for me), the adjective describing it goes generally before the noun.
The translation displayed above is NOT what I was told was the correct answer.
I was shown: "Su documento es una extensa charla." My first issue is that when it comes to documents, "long" and "extensive" are NOT synonyms, even if they may frequently go hand-in-hand -- a document might be long but extremely shallow. Extensive strongly suggests it has depth, no matter the length.
Also, "charla" is a "chat", NOT a word that one associates with the words "document" or "discussion". Tell me why I shouldn't take offense that I was told that a document that is a long discussion is a "chat"?