Editing Mon language (section)

=== Vocalic register ===
Unlike the surrounding Burmese and [[Thai language|Thai]] languages, Mon is not a [[tone (linguistics)|tonal language]]. As in many Mon–Khmer languages, Mon uses a vowel-phonation or vowel-[[register (phonology)|register]] system in which the quality of voice in pronouncing the vowel is phonemic. There are two registers in Mon:

# Clear (modal) voice, analyzed by various linguists as ranging from ordinary to [[Creaky voice|creaky]]
# [[Breathy voice]], vowels have a distinct breathy quality

One study involving speakers of a Mon dialect in Thailand found that in some syllabic environments, words with a breathy voice vowel are significantly lower in pitch than similar words with a clear vowel counterpart.<ref name=thongkum>[[Theraphan Luangthongkum|Thongkum, Theraphan L]]. 1988. The interaction between pitch and phonation type in Mon: phonetic implications for a theory of tonogenesis. ''[[Mon-Khmer Studies]]'' 16-17:11-24.</ref> While difference in pitch in certain environments was found to be significant, there are no [[minimal pair]]s that are distinguished solely by pitch. The contrastive mechanism is the vowel phonation.

In the examples below, breathy voice is marked with under-diaeresis.