linguistic:translation, stylistic:tone
ISO classification

Since the year 2000, ISO 639 classification recognizes Serbo-Croatian only as a ' macrolanguage ', having removed its original codes from ISO 639-1 and ISO 639-2 standards. That left the ISO 639-3 'macrolanguage' (a book-keeping device in the ISO 639-3 standard to keep track of which ISO 639-3 codes correspond with which ISO 639-2 codes) stranded without a corresponding ISO 639-2 code.