The Morpheme Marking Definite Past /-DI/
The past tense morpheme applies to verbs, and it has eight allomorphs determined
by the preceding stem vowel and consonant. The high suffix vowel and the stem
are supposed to share the specification for both backness and rounding. In addition,
stem consonants and suffix consonants should share the same voicing feature: /d/
is selected after the voiced consonats and /t/ after the voiceless.