A language may use different sets of symbols or rules for distinct vocabulary items, typically for foreign words, such as in the Japanese katakana syllabary is used for foreign words, and there are rules in English for using loanwords from other languages.
ɐ lˈæŋɡwɪdʒ mˈeɪ jˈuːz dˈɪfɹənt sˈɛts ʌv sˈɪmbəlz ɔːɹ ɹˈuːlz fɔːɹ dɪstˈɪŋkt voʊkˈæbjʊlˌɛɹi ˈaɪɾəmz, tˈɪpɪkli fɔːɹ fˈɔːɹən wˈɜːdz, sˈʌtʃ ɐz ɪnðə dʒˌæpənˈiːz kˌæɾɐkˈɑːnə sˈɪlɐbˌɛɹi ɪz jˈuːzd fɔːɹ fˈɔːɹən wˈɜːdz, ænd ðɛɹˌɑːɹ ɹˈuːlz ɪn ˈɪŋɡlɪʃ fɔːɹ jˈuːzɪŋ lˈoʊnwɜːdz fɹʌm ˈʌðɚ lˈæŋɡwɪdʒᵻz.