Pronunciation of individual words may change according to the presence of surrounding words in a sentence, for example, in Sandhi.
pɹənˌʌnsɪˈeɪʃən ʌv ˌɪndᵻvˈɪdʒuːəl wˈɜːdz mˈeɪ tʃˈeɪndʒ ɐkˈoːɹdɪŋ tə ðə pɹˈɛzəns ʌv sɚɹˈaʊndɪŋ wˈɜːdz ɪn ɐ sˈɛntəns, fɔːɹ ɛɡzˈæmpəl, ɪn sˈændhaɪ.