Should this also accept "The office is next to/near the library" as the wording (to my knowledge) is the same?
Yes, it does and it is
If ”lângă” cannot be translated as ”next to”, what is the translation for ”next to”?
"next to" should be accepted as a translation of "lângă".
Is there a difference between bookcase and bookshelf? I never heared of a bookcase before.
A bookshelf is one shelf for books. A bookcase contains several shelves.
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