Editing Old Prussian language (section)

===Vowels===
The following description is based on the phonological analysis by Schmalstieg:<ref name="Schmalstieg2005">{{cite journal|title=Vytautas Mažiulis. Prūsų kalbos istorinė gramatika: recenzija|trans-title=Vytautas Mažiulis. Historical grammar of the Prussian language: A review|journal=Baltu filoloģija|date=2005|volume=14|issue=1|first=William Riegel|last=Schmalstieg|publisher= Latvijas Universitāte|pages=159{{Hyphen}}163|language=en|issn=1691-0036}}</ref>
{| class="wikitable" style="text-align:center"
! colspan="2" rowspan="2" |
! colspan="2" |[[Front vowel|Front]]
! colspan="2" |[[Central vowel|Central]]
! colspan="2" |[[Back vowel|Back]]
|-
!<small>short</small> !! <small>long</small>
!<small>short</small> !! <small>long</small>
!<small>short</small> !! <small>long</small>
|-
!colspan="2" |[[High vowel|High]]
| align="center" |{{IPA link|i}}
|align="center" |{{IPA link|iː}}
|
|
| align="center" |{{IPA link|u}}
| align="center" |{{IPA link|uː}}
|-
!colspan="2" |[[Mid vowel|Mid]]
|{{IPA link|e}}
|{{IPA link|eː}}
|
|
|
|{{IPA link|oː}}
|-
!colspan="2" |[[Low vowel|Low]]
|
|
|{{IPA link|a}}
|{{IPA link|aː}}
|
|
|}

* {{IPA|/a, a:/}} could also have been realized as {{IPA|[ɔ, ɔ:]}}
* {{IPA|/oː/}} is not universally accepted, p.e. by Levin (1975)<ref>{{cite journal|journal=General Linguistics|volume=15|issue=3|pages=144–158|year=1975|first=Jules|last=Levin|title=Dynamic Linguistics and Baltic Historical Phonology|place=London, University Park|publisher=Pennsylvania State University Press}}</ref>

====Diphthongs====
Schmalstieg proposes three native diphthongs:{{r|Schmalstieg|pp=19{{Hyphen}}20}}

{| class="wikitable" style="text-align:center"
!
![[Front vowel|Front]]
![[Back vowel|Back]]
|-
![[Mid vowel|Mid]]
|{{IPA|ei}}
|
|- align="center"
![[Open vowel|Open]]
|{{IPA|ai}}
|{{IPA|au}}
|}

* {{IPA|/au/}} may have also been realized as a mid-back diphthong {{IPA|[eu]}} after palatalized consonants.
* {{IPA|/ui/}} occurs in the word {{lang|prg|cuylis}}, which is thought to be a loanword.