Editing Isan language (section)

==Phonology==
===Consonants===
====Initials====
Isan shares its consonant inventory with the Lao language whence it derives. The [[stop consonant|plosive]] and [[affricate consonant|affricate]] consonants can be further divided into three [[voice-onset time]]s of [[voiced consonant|voiced]], [[tenuis consonant|tenuis]] and [[aspirated consonant|aspirated]] consonants. For example, Isan has the plosive set of voiced {{IPAslink|b}}, tenuis {{IPAslink|p}} which is like the 'p' in 'spin' and aspirated {{IPAslink|pʰ}} like the 'p' in 'puff'. Isan and Lao lack the sound {{IPAslink|tɕʰ}} and its allophone {{IPAslink|ʃ}} of Thai, replacing these sounds with {{IPAslink|s}} in analogous environments. Similarly, {{IPAslink|r}} is rare. Words in Isan and Lao cognate to Thai word with {{IPAslink|r}} have either {{IPAslink|h}} or {{IPAslink|l}} in their place, although educated speakers in Isan or Laos may pronounce some words with {{IPAslink|r}}. In Central and Southern Thai, words with {{IPAslink|r}} may be pronounced as {{IPAslink|l}} ([[lambdacism]]) in casual environments although this is frowned upon in formal or cultivated speech.

Unlike Central and Southern Thai, Isan and Lao have a {{IPAslink|j}}–{{IPAslink|ɲ}} distinction, whereas cognate words from Isan and Lao with {{IPAslink|ɲ}} are all {{IPAslink|j}} in Central and Southern Thai. Substitution of {{IPAslink|w}} with {{IPAslink|ʋ}}, which is not used in Thai, is common in large areas of both Laos and Isan but is not universal in either region, but is particularly associated with areas influenced by Vientiane and Central Lao dialects. The glottal stop occurs any time a word begins with a vowel, which is always built around a null consonant.

{| class="wikitable" style="text-align:center;"
|+ Isan consonant distribution with Thai and Lao alphabets.
! colspan="2" | 
! [[Labial consonant|Labial]]
! [[Dental consonant|Dental]]/[[Alveolar consonant|Alveolar]]
! ([[Alveolo-palatal consonant|Alveolo-]]) [[Palatal consonant|Palatal]]
! [[Velar consonant|Velar]]
! [[Glottal consonant|Glottal]]
|-
! colspan="2" | [[Nasal consonant|Nasal]]
| {{IPAslink|m}} ม, หม{{ref|ligature|4}}ມ, ໝ{{ref|ligature|4}}/ຫມ{{ref|ligature|4}}
| {{IPAslink|n}} ณ{{ref|Sanskrit|1}}, น, หน{{ref|ligature|4}}ນ, ໜ{{ref|ligature|4}}/ຫນ{{ref|ligature|4}}
| {{IPAslink|ɲ}}{{ref|NotThai|2}}<sup>,</sup>{{ref|LaoFinal|5}} ญ{{ref|ThaiY|3}}, ย{{ref|ThaiY|3}}, หญ{{ref|ThaiY|3}}<sup>,</sup>{{ref|ligature|4}}, หย{{ref|ThaiY|3}}<sup>,</sup>{{ref|ligature|4}}ຍ{{ref|LaoFinal|5}}, ຫຽ{{ref|ligature|4}}<sup>,</sup>{{ref|OldLao|11}}/ຫຍ{{ref|ligature|4}}
| {{IPAslink|ŋ}} ง, หง{{ref|ligature|4}}ງ, ຫງ{{ref|ligature|4}}
|
|-
! rowspan="3" | [[Plosive]]/<br>[[Affricate]]
! <small>[[Voicelessness|voiceless]]</small>
| {{IPAslink|p}} ป ປ
| {{IPAslink|t}} ฏ{{ref|Sanskrit|1}},ต ຕ
| {{IPAslink|tɕ}} จ ຈ
| {{IPAslink|k}} ก ກ
| {{IPAslink|ʔ}}{{ref|glottalstop|10}} อ{{ref|glottalstop|10}} ອ{{ref|glottalstop|10}}
|-
! <small>[[Voicelessness|voiceless]] [[Aspirated consonant|aspirated]]</small>
| {{IPAslink|pʰ}} ผ, พ, ภ
ຜ, ພ
| {{IPAslink|tʰ}} ฐ{{ref|Sanskrit|1}}, ฑ{{ref|Sanskrit|1}}, ฒ{{ref|Sanskrit|1}}, ถ, ท, ธ
ຖ, ທ
| {{IPAslink|tɕʰ}}{{ref|ThaiCH|6}} ฉ{{ref|ThaiCH|6}}, ช{{ref|ThaiCH|6}}, ฌ{{ref|Sanskrit|1}}<sup>,</sup>{{ref|ThaiCH|6}}ຊ{{ref|ThaiCH|6}}
| {{IPAslink|kʰ}} ข, ฃ{{ref|obsolete|7}}, ค, ฅ{{ref|obsolete|7}}, ฆ{{ref|Sanskrit|1}}ຂ, ຄ
|
|-
! <small>[[Voice (phonetics)|voiced]]</small>
| {{IPAslink|b}} บ ບ
| {{IPAslink|d}} ฎ{{ref|Sanskrit|1}}, ด ດ
|
|
|
|-
! colspan="2" | [[Fricative consonant|Fricative]]
| {{IPAslink|f}} ฝ, ฟ
ຝ, ຟ
| {{IPAslink|s}} ซ, ศ{{ref|Sanskrit|1}}, ษ{{ref|Sanskrit|1}}, ส
ສ, ຊ
|
| {{IPAblink|x}}{{ref|Dialect|13}} ข, ฃ{{ref|obsolete|7}}, ค, ฅ{{ref|obsolete|7}}, ฆ{{ref|Sanskrit|1}}ຂ, ຄ
| {{IPAslink|h}} ห, ฮ{{ref|LaoH|9}}ຫ, ຮ{{ref|LaoH|9}}
|-
! colspan="2" | [[Approximant consonant|Approximant]]
| {{IPAblink|ʋ}}{{ref|NotThai|2}}<sup>,</sup>{{ref|LaoFinal|5}} ว{{ref|LaoFinal|5}}, หว{{ref|ligature|4}}ວ{{ref|LaoFinal|5}}, ຫວ{{ref|ligature|4}}
| {{IPAslink|l}} ล, ฬ{{ref|Sanskrit|1}}, ร{{ref|informal|12}}, หล{{ref|ligature|4}}, หร{{ref|ligature|4}}<sup>,</sup>{{ref|informal|12}}ຣ{{ref|OldLao|11}}, ລ, ຫຼ{{ref|ligature|4}}/ຫລ{{ref|ligature|4}}, ຫຼ{{ref|ligature|4}}<sup>,</sup>{{ref|OldLao|11}}/ຫຣ{{ref|ligature|4}}<sup>,</sup>{{ref|OldLao|11}}
| {{IPAslink|j}} ย, อย, หย{{ref|ligature|4}}ຢ, ຫຽ{{ref|ligature|4}}<sup>,</sup>{{ref|OldLao|11}}
| {{IPAslink|w}} ว, หว{{ref|ligature|4}}ວ, ຫວ{{ref|ligature|4}}
|
|-
! colspan="2" | [[Rhotic consonant|Rhotic]]/[[Liquid consonant|Liquid]]
|
| {{IPAslink|r}}{{ref|LaoR|8}} ร{{ref|LaoR|8}}, หร{{ref|ligature|4}}<sup>,</sup>{{ref|LaoR|8}}
ຣ{{ref|LaoR|8}}<sup>,</sup>{{ref|OldLao|11}}, ຫຼ{{ref|ligature|4}}<sup>,</sup>{{ref|LaoR|8}}/ຫຣ{{ref|ligature|4}}<sup>,</sup>{{ref|LaoR|8}}<sup>,</sup>{{ref|OldLao|11}}
|
|
|
|}
*{{note|Sanskrit|1}} Only used in Sanskrit or Pali loan words.
*{{note|NotThai|2}} Unique to Isan and Lao, does not occur in Thai but {{IPAslink|ʋ}} is only an allophone of {{IPAslink|w}} whereas {{IPAslink|ɲ}} is phonemic.
*{{note|ThaiY|3}} Central and Southern Thai spelling does not distinguish {{IPAslink|j}} from {{IPAslink|ɲ}}.
*{{note|ligature|4}} Lao ligature of silent {{IPAslink|h}} (ຫ) or digraph; Thai digraph with silent {{IPAslink|h}} (ห).
*{{note|LaoFinal|5}} Only as syllable-initial consonants.
*{{note|ThaiCH|6}} Use of {{IPAslink|tɕʰ}} is Thai interference in Isan and rare in Laos, usually interference from a northern tribal Tai language, almost always {{IPAslink|s}}.
*{{note|obsolte|7}} Still taught as part of the alphabet, 'ฃ' and 'ฅ' are obsolete and have been replaced by 'ข' and 'ค', respectively.
*{{note|LaoR|8}} Mark of interference from Isan or erudition in Laos. Usually replaced by {{IPAslink|l}} and even by 'ລ' {{IPAslink|l}} in modern Lao writing.
*{{note|LaoH|9}} Used to mark {{IPAslink|h}} in words that are etymologically {{IPAslink|r}}.
*{{note|glottalstop|10}} All words that begin with vowels must be written with the anchor consonant and are pronounced with a glottal stop.
*{{note|OldLao|11}} Generally used in pre-1970s Lao.
*{{note|informal|12}} Only in very casual, informal Thai.
*{{note|Dialect|13}} Allophone of {{IPAslink|kʰ}} in some dialects.

====Clusters====
Consonant clusters are rare in spoken Lao as they disappear shortly after the adoption of writing. In native words, only /kw/ and /kʰw/ are permissible, but these can only occur before certain vowels due to the [[diphthongization]] that occurs before the vowels /aC/, /am/, /aː/ and /aːj/. Isan speakers, who are educated in Thai and often use Thai spelling of etymological vocabulary to transcribe Isan, will generally not pronounce consonant clusters but may do so when code-switching to Thai or when pronouncing high-brow words of Sanskrit, Pali or Khmer derivation. Lao speakers from Laos will sometimes pronounce clusters in these borrowed loan words, but this is restricted to aging speakers of the Laotian diaspora.

{| class="wikitable" style="text-align:center;"
|+ Lack of consonant clusters in Isan 
|-
! colspan="2" | Isan
! colspan="2" | Thai
! colspan="2" | Lao
! colspan="2" | Isan
! colspan="2" | Thai
! colspan="2" | Lao
! colspan="2" | Isan
! colspan="2" | Thai
! colspan="2" | Lao
|-
| ก
| rowspan="3" | {{IPA|/k/}}
| ก
| {{IPA|/k/}}
| rowspan="3" | ກ
| rowspan="3" | {{IPA|/k/}}
| ค
| rowspan="3" | {{IPA|/kʰ/}}
| ค
| {{IPA|/kʰ/}}
| rowspan="3" | ຄ
| rowspan="3" | {{IPA|/kʰ/}}
| ป
| rowspan="3" | {{IPA|/p/}}
| ป
| {{IPA|/p/}}
| rowspan="3" | ປ
| rowspan="3" | {{IPA|/p/}}<br />
|-
| กร
| กร
| {{IPA|/kr/}}
| คร
| คร
| {{IPA|/kʰr/}}
| ปร
| ปร
| {{IPA|/pr/}}
|-
| กล
| กล
| {{IPA|/kl/}}
| คล
| คล
| {{IPA|/kʰl/}}
| ปล
| ปล
| /pl/
|-
| กว{{ref|LaoDiph|1}}
| {{IPA|/kw/}}{{ref|LaoDiph|1}}
| กว
| /kw/
| ກວ{{ref|LaoDiph|1}}
| {{IPA|/kw/}}{{ref|LaoDiph|1}}
| คว{{ref|LaoDiph|1}}
| {{IPA|/kʰw/}}{{ref|LaoDiph|1}}
| คว
| {{IPA|/kʰw/}}
| ຄວ{{ref|LaoDiph|1}}
| /kʰw/{{ref|LaoDiph|1}}
| ผ
| rowspan="2" | {{IPA|/pʰ/}}
| ผ
| {{IPA|/pʰ/}}
| rowspan="2" | ຜ
| rowspan="2" | {{IPA|/pʰ/}}
|-
| ข
| rowspan="3" | {{IPA|/kʰ/}}
| ข
| {{IPA|/kʰ/}}
| rowspan="3" | ຂ
| rowspan="3" | {{IPA|/kʰ/}}
| ต
| rowspan="2" | {{IPA|/t/}}
| ต
| {{IPA|/t/}}
| rowspan="2" | ຕ
| rowspan="2" | {{IPA|/t/}}
| ผล
| ผล
| {{IPA|/pʰl/}}
|-
| ขร
| ขร
| {{IPA|/kʰr/}}
| ตร
| ตร
| {{IPA|/tr/}}
| พ
| rowspan="3" | {{IPA|/pʰ/}}
| พ
| {{IPA|/pʰ/}}
| rowspan="3" | ພ
| rowspan="3" | {{IPA|/pʰ/}}
|-
| ขล
| ขล
| {{IPA|/kʰl/}}
| rowspan="2" colspan="6" | 
| พร
| พร
| {{IPA|/pʰr/}}
|-
| ขว{{ref|LaoDiph|1}}
| {{IPA|/kʰw/}}{{ref|LaoDiph|1}}
| ขว
| {{IPA|/kʰw/}}
| ຂວ{{ref|LaoDiph|1}}
| {{IPA|/kʰw}}/{{ref|LaoDiph|1}}
| พล
| พล
| {{IPA|/pʰl/}}
|}
*{{note|LaoDiph|1}} Before /aC/, /aː/, /aːj/ and /am/ [[diphthongization]] occurs which assimilates the {{IPA|/w/}} so it is only a true cluster in other vowel environments, only occurs in Isan and Lao.

====Finals====
Isan shares with both Lao and Thai a restrictive set of permissible consonant sounds at the end of a syllable or word. Isan, using its current method of writing according to Thai etymological spelling, preserves the spelling to imply the former sound of borrowed loan words even if the pronunciation has been assimilated. Due to spelling reforms in Laos, the letters that can end a word were restricted to a special set of letters, but older writers and those in the Lao diaspora occasionally use some of the more etymological spellings.

In pronunciation, all [[plosive consonant|plosive sounds]] (besides the [[glottal stop]] /ʔ/) are [[unreleased stop|unreleased]], as a result, there is no voicing of final consonants or any release of air. The finals {{IPA|/p/}}, {{IPA|/t/}} and {{IPA|/k/}} are thus actually pronounced {{IPA|[p̚]}}, {{IPA|[t̚]}}, and {{IPA|[k̚]}}, respectively.

Of the consonant letters, excluding the disused ฃ and ฅ, six (ฉ ผ ฝ ห อ ฮ) cannot be used as a final and the other 36 are grouped as following.

{| class="wikitable" style="text-align:center;"
|+ Isan final consonants with Lao script for comparison
|- style="font-weight:bold;"
! style="font-weight:normal;" | 
! colspan="2" | Labial
! colspan="2" | Alveolar
! Palatal
! colspan="2" | Velar
! Glottal
|-
! rowspan="3" | Nasal
| colspan="2" | {{IPAslink|m}}<br />
| colspan="2" | {{IPAslink|n}}<br />
| rowspan="6" | 
| colspan="2" | {{IPAslink|ŋ}}
| rowspan="3" style="text-align:left;" | 
|-
| colspan="2" | ม
| colspan="2" | ญ, ณ, น, ร, ล, ฬ
| colspan="2" | ง
|-
| colspan="2" | ມ
| ນ{{ref|only|1}}
| ຣ{{ref|oldish|2}}, ລ{{ref|oldish|2}}
| colspan="2" | ງ
|-
! rowspan="3" | Plosive
| colspan="2" | {{IPAslink|p}}
| colspan="2" | {{IPAslink|t}}
| colspan="2" | {{IPAslink|k}}
| {{IPAslink|ʔ}}
|-
| colspan="2" | บ, ป, พ, ฟ, ภ
| colspan="2" | จ, ช, ซ, ฌ, ฎ, ฏ, ฐ, ฑ, ฒ, ด, ต, ถ, ท, ธ, ศ, ษ, ส
| colspan="2" | ก, ข, ค, ฆ
| rowspan="2" | *{{ref|glottal stop|3}}
|-
| ບ{{ref|only|1}}
| ປ{{ref|oldish|2}}, ພ{{ref|oldish|2}}, ຟ{{ref|oldish|2}}
| ດ{{ref|only|1}}
| ຈ{{ref|oldish|2}}, ສ{{ref|oldish|2}}, ຊ{{ref|oldish|2}}, ຕ{{ref|oldish|2}}, ຖ{{ref|oldish|2}}, ທ{{ref|oldish|2}}
| ກ{{ref|only|1}}
| ຂ{{ref|oldish|2}}, ຄ{{ref|oldish|2}}
|-
! rowspan="3" | Approximant
| colspan="2" | /w/{{ref|vowel|4}}
| rowspan="3" colspan="2" | 
| /j/{{ref|vowel|4}}
| rowspan="3" colspan="3" | 
|- style="text-align:left;"
| colspan="2" style="text-align:center;" | ว
| style="text-align:center;" | ย
|- style="text-align:left;"
| colspan="2" style="text-align:center;" | ວ
| style="text-align:center;" | ຍ
|}
*{{note|only|1}} Where alternative spellings once existed, only these consonants can end words in modern Lao.
*{{note|oldish|2}} Used in pre-1970s Lao spelling as word-final letters.
*{{note|glottal stop|3}} Glottal stop is unwritten but is pronounced at the end of short vowels that occur at the end of a consonant.
*{{note|vowel|4}} These occur only as parts of diphthongs or triphthongs and are usually included as parts of vowels.

===Vowels===
The vowel structure of Isan is the similar as the central and southern Lao dialects of Laos. The vowel quality is also similar to Thai, but differs in that the two back vowels, [[close back unrounded vowel]] /ɯ/ and the [[close-mid back unrounded vowel]] /ɤ/, centralized as the [[close central unrounded vowel]] /ɨ/ and the [[mid central vowel]] /ə/ in some speakers, respectively, as well as in diphthongs that may include these sounds. To Thai speakers, Isan and Lao vowels tend to have a nasal quality.

In many cases, especially diphthongs with /u/ as first element is lengthened in Isan as it is in Standard Lao, so that the word ''tua'' which means 'body' ({{langx|th|ตัว}}, written the same in Isan) is pronounced {{IPA|/tua/}} in Thai but in Isan as {{IPA|/tuːa/}} in some dialects, similar to {{langx|lo|ຕົວ}}. The symbol '◌' indicates the required presence of a consonant, or for words that begin with a vowel sound, the 'null consonant' 'อ' or its Lao equivalent, 'ອ', which in words that begin with a vowel, represents the glottal stop /ʔ/. Short vowels that end with '◌ะ' or Lao '◌ະ' also end with a glottal stop.

Thai and Lao are both [[abugida]] scripts, so certain vowels are pronounced without being written, taking the form of /a/ in open syllables and /o/ in closed syllables, i.e., ending in a consonant. For example, the Khmer loan word ''phanom'' or 'hill' found in many place names in Isan is {{langx|tts|พนม}} or 'PH-N-M' but pronounced {{IPA|/pʰàʔ.no᷇m/}}, with 'PH' as the open syllable and 'N-M' as the closed syllable. In Lao orthography, inherited from Tai Noi, closed syllables are marked with a 'ົ' over the consonants and the /a/ of open syllables was unwritten, thus {{langx|lo|ພນົມ}} or 'Ph-N-<sup>o</sup>-M'. In current practice as a result of spelling reforms, all vowels are written out and in modern {{langx|lo|ພະນົມ}} or 'Ph-a-N-<sup>o</sup>-M' is more common thus modern Lao is no longer a true abugida.

{| class="wikitable" style="text-align:center;"
|+ Isan vowel distribution
|- style="font-weight:bold; vertical-align:middle; background-color:#EAECF0; color:#202122;"
! style="text-align:left;" | 
! [[Front vowel|Front]]
! [[Central vowel|Central]]
! [[Back vowel|Back]]
|- style="vertical-align:middle; background-color:#F8F9FA; color:#202122;"
! style="text-align:left;" | [[Close vowel|Close]]
| {{IPAslink|i}}
| {{IPAslink|ɨ}} ~ {{IPAslink|ɯ}}
| {{IPAslink|u}}
|- style="vertical-align:middle; background-color:#F8F9FA; color:#202122;"
! style="text-align:left;" | [[Mid vowel|Mid]]
| {{IPAslink|e}}
| {{IPAslink|ə}} ~ {{IPAslink|ɤ}}
| {{IPAslink|o}}
|- style="vertical-align:middle; background-color:#F8F9FA; color:#202122;"
! style="text-align:left;" | [[Open vowel|Open]]
| {{IPAslink|ɛ}}
| {{IPAslink|ä|a}}
| {{IPAslink|ɔ}}
|}

====Vowel length====
Vowels usually exist in long-short pairs determined by [[vowel length]] which is [[phoneme|phonemic]], but vowel length is not indicated in the RTGS romanization commonly used in Thailand or the BGN/PCGN French-based scheme commonly used in Laos. The Isan word romanized as ''khao'' can represent both {{langx|tts|เขา}} {{IPA|/kʰǎw/}}, 'he' or 'she', and {{langx|tts|ขาว}} {{IPA|/kʰǎːw/}}, 'white' which corresponds to {{langx|lo|ເຂົາ}} and {{langx|lo|ຂາວ}}, respectively, which are also romanized as ''khao''. In these cases, the pairs of words have the same tone and pronunciation and are differentiated solely by vowel length.

{| class="wikitable" 
|+ Isan Long-Short Vowel Pairs (Thai Script/Lao Pronunciation)
! colspan="4" | Long vowels
! colspan="4" | Short vowels
|-
| Thai
| IPA
| Lao
| IPA
| Thai
| IPA
| Lao
| IPA
|-
| colspan="4";|
| ◌ำ
| /am/
| ◌ຳ
| /am/
|-
| ◌า
| /aː/
| ◌າ
| /aː/
| ◌ะ, ◌ั, *{{ref|assumed|1}} 
| /aʔ/, /a/
| ◌ະ, ◌ັ
| /aʔ/, /a/
|-
| ◌ี
| /iː/
| ◌ີ 
| /iː/
| ◌ิ
| /i/
| ◌ິ 
| /i/
|-
| ◌ู
| /uː/
| ◌ູ
| /uː/
| ◌ุ
| /u/
| ◌ຸ
| /u/
|-
| เ◌
| /eː/
| ເ◌
| /eː/
| เ◌ะ, เ◌็
| /eʔ/, /e/
| ເ◌ະ, ເ◌ົ 
| /eʔ/, /e/
|-
| แ◌
| /ɛː/
| ແ◌
| /ɛː/
| แ◌ะ, แ◌็
| /ɛʔ/, /ɛ/
| ແ◌ະ, ແ◌ົ 
| /ɛʔ/, /ɛ/
|-
| ◌ื, ◌ือ 
| /ɯː/
| ◌ື 
| /ɯː/
| ◌ื
| /ɯ/
| ◌ຶ
| /ɯ/
|-
| เ◌อ, เ◌ิ 
| /ɤː/
| ເີ◌ 
| /ɤː/
| เ◌อะ
| /ɤʔ/
| ເິ◌ 
| /ɤʔ/
|-
| โ◌
| /oː/
| ໂ◌
| /oː/
| โ◌ะ, *{{ref|asssumed|2}}
| /oʔ/, /o/
| ໂ◌ະ, ◌ົ 
| /oʔ/, /o/
|-
| ◌อ
| /ɔː/
| ◌ອ◌, ◌ໍ
| /ɔː/
| เ◌าะ
| /ɔʔ/
| ເ◌າະ
| /ɔʔ/
|}
*{{note|assumed|1}} Unwritten in open syllables.
*{{note|asssumed|2}} Unwritten in closed syllables.

====Diphthongs====
{| class="wikitable" 
|+ Isan Diphthongs<br />(Thai Script/Lao Pronunciation)
! colspan="4" | Long vowels
! colspan="4" | Short vowels
|-
! Thai
! IPA
! style="width: 11em; | Lao
! IPA
! Thai
! IPA
! style="width: 11em; | Lao
! IPA
|-
| colspan="4"|
| ◌วำ{{ref|ThaiWam|3}} 
| /wam/
| ◌ວຳ 
| /uam/
|-
| ◌าย
| /aːj/
| ◌າຍ/◌າຽ{{ref|OldLao|2}}
| /aːj/
| ไ◌{{ref|long|1}}, ใ◌{{ref|long|1}}, ไ◌ย, ◌ัย
| /aj/
| ໄ◌{{ref|long|1}}, ໃ◌{{ref|long|1}}, ໄ◌ຍ{{ref|long|1}}<sup>,</sup>{{ref|OldLao|2}}/ໄ◌ຽ{{ref|OldLao|2}}, ◌ັຍ{{ref|OldLao|2}}/◌ັຽ{{ref|OldLao|2}} 
| /aj/
|-
| ◌าว 
| /aːw/
| ◌າວ 
| /aːw/
| เ◌า{{ref|long|1}}
| /aw/
| ເ◌ົາ{{ref|long|1}}
| /aw/
|-
| colspan="4";|
| ◌ิว
| /iw/
| ◌ິວ
| /iw/
|-
| เ◌ีย
| /ia/
| ເ◌ຍ/ເ◌ັຽ{{ref|OldLao|2}}, ◌ຽ◌
| /ia/
| เ◌ียะ
| /iaʔ/
| ເ◌ັຍ/ເ◌ັຽະ{{ref|OldLao|2}}
| /iaʔ/
|-
| ◌อย 
| /ɔːj/
| ◌ອຍ/◌ອຽ{{ref|OldLao|2}} /◌ຽ{{ref|OldLao|2}} 
| /ɔːj/
| rowspan="2" colspan="4";|
|-
| โ◌ย
| /oːj/
| ໂ◌ຍ/ໂ◌ຽ{{ref|OldLao|2}} 
| /oːj/
|-
| เ◌ือ, เ◌ือ◌ 
| /ɯa/
| ເ◌ືອ, ເ◌ືອ◌ 
| /ɯa/
| เ◌ือะ
| /ɯaʔ/
| ເ◌ຶອ
| /ɯaʔ/
|-
| ◌ัว, ◌ว◌
| /ua/
| ◌ັວ, ◌ວ◌, ◌ວາ, 
| /ua/
| ◌ัวะ
| /uaʔ/
| ◌ົວະ,
| /uaʔ/
|-
| ◌ูย 
| /uːj/
| ◌ູຍ/◌ູຽ{{ref|OldLao|2}}
| /uːj/ 
| ◌ຸย 
| /uj/
| ◌ຸຍ/◌ຸຽ{{ref|OldLao|2}} 
| /uj/
|-
| เ◌ว
| /eːw/
| ເ◌ວ 
| /eːw/
| เ◌็ว
| /ew/
| ເ◌ັວ
| /ew/
|-
| แ◌ว
| /ɛːw/
| ແ◌ວ 
| /ɛːw/
| rowspan="2" colspan="4";|
|-
| เ◌ย 
| /ɤːj/ 
| ເ◌ີຍ/ເ◌ີຽ{{ref|OldLao|2}} 
| /ɤːj/
|}
*{{note|long|1}} Considered long vowels for the purpose of determining tone.
*{{note|OldLao|2}} Archaic usage common in pre-1970s Lao.
*{{note|ThaiWam|3}} The Thai vowel 'ำ' is a short vowel. In Isan, it is diphthongized after /w/ into /uam/.

====Triphthongs====
{| class="wikitable" 
|+ Isan Triphthongs<br />(Thai Script/Lao Pronunciation)
!Thai
!IPA
!Lao
!IPA
|-
| เ◌ียว{{ref|long|1}}
| {{IPA|/iaw/}}
| ◌ຽວ{{ref|long|1}}
| {{IPA|/iaw/}}
|-
| ◌วย{{ref|long|1}}
| {{IPA|/uaj/}}
| ◌ວຍ/◌ວຽ{{ref|long|1}}<sup>,</sup>{{ref|OldLao|2}} 
| {{IPA|/uaj/}}
|-
| เ◌ือย{{ref|long|1}}
| {{IPA|/ɯaj/}}
| ເ◌ືວຍ{{ref|long|1}}/ເ◌ືວຽ{{ref|long|1}}<sup>,</sup>{{ref|OldLao|2}}
| {{IPA|/ɯaj/}}
|}
*{{note|long|1}} Considered long vowels for the purpose of determining tone.
*{{note|OldLao|2}} Archaic usage common in pre-1970s Lao.

====Tones====
{| class="wikitable"
|-----bgcolor="#eeeeee"
|+ Isan Tone Distribution (Khon Kaen-Roi Et)<ref>{{cite journal |last1=Hartmann |first1=J. |year=1971 |url=http://www.siamese-heritage.org/jsspdf/1971/JSS_068_1g_Hartmann_AlignmentOfDialectsInSouthwesternTai.pdf |title=A model for the alignment of dialects in southwestern Tai |archive-url=https://web.archive.org/web/20210418090250/http://www.siamese-heritage.org/jsspdf/1971/JSS_068_1g_Hartmann_AlignmentOfDialectsInSouthwesternTai.pdf |archive-date=2021-04-18 |journal=Journal of the Siam Society |volume=65 |issue=2 |pages=72–87 }}</ref>
||'''Tone Class'''||'''Inherent Tone'''||'''Mai ek ({{lang|th|อ่}})'''||'''Mai tho ({{lang|th|อ้}})'''||'''Long Vowel'''||'''Short Vowel'''
|----- bgcolor="#ffffff"
! High
|| Rising
|| Mid
|| Low
|| Low
|| Mid-low
|----- bgcolor="#ffffff"
! Middle
|| Low
|| High
|| Falling
|| Low
|| Rising
|----- bgcolor="#ffffff"
! Low
|| Falling
|| Mid
|| Mid-low
|| Falling
|| Low
|}