Vowel the vowel sounds of "flower", , form a triphthong or disyllable, depending on dialect. In phonology, diphthongs and triphthongs are distinguished from sequences of monophthongs by whether the vowel sound may be analyzed into different phonemes or not. For example, the vowel sounds in a two-syllable pronunciation of the word "flower" () phonetically form a disyllabic triphthong, but are phonologically a sequence of a diphthong (represented by the letters ) and a monophthong (represented by the letters ). Some linguists use the terms "diphthong" and "triphthong" only in this phonemic sense. The name "vowel" is often used for the symbols
Iu Mien language represented in the Iu Mien United Script using combinations of the six letters, , , , , , and . According to Bruhn, the monophthongs are , , , , , , , , , and . The diphthongs are , , , , , , , . Furthermore, additional diphthongs and triphthongs can be formed from the aforementioned vowels through /i/- or /u/-on-gliding (having /i/ or /u/ before the vowel). Such vowels attested by Bruhn include , , , , , , , , , , , , , , , , , , , , and . The