Observation
kunu(n) there is snow apu kunut there isn’t any snow

A verb like kunu(n) is actually kunu in the eastern dialect and kunun in the western dialect. In other words, they are verbs for which the stem alternates according to the dialect: u or un.

In the eastern dialects, verbs like kunu(n) are conjugated like II verbs ending in -u.

In the western dialects, the conjugation is mixed: it is like pańi verbs (for example pikupańu it’s brokenpikupańńu hers/his is broken) in the independent and in certain modes of the conjunct (indirect and unrealized); and it is like u-stem verbs in the conjunct indicative and in the conjunct subjunctive (apu pimikut it does not go by on the water).

II VERBS WITH u STEMS (EASTERN DIALECTS) AND un STEMS (WESTERN DIALECTS)
kunu kunuipan apu kunut
kunun kununipan
there is snow there was snow there isn’t any snow
uińnu uińnuipan apu uińnut
uińnun uińnunipan
it is fatty it was fatty it isn’t fatty
ashiniu ashiniuipan apu ashiniut
ashiniun ashiniunipan
it is in stone it was in stone it isn’t in stone
shuńiau shuńiauipan apu shuńiaut
shuńiaun shuńiaunipan
it’s expensive it was expensive it isn’t expensive
shipissu shipissuipan apu shipissut
shipissun shipissunipan
it’s a brook it was a brook it isn’t a brook
pimiku pimikuipan apu pimikut
pimikun pimikunipan
it goes by on the water it went by on the water it doesn’t go by on the water
katshiteu katshiteuipan apu katshiteut
katshiteun katshiteunipan
it is charcoal it was charcoal it isn’t charcoal
uashtessiu uashtessiuipan apu uashtessiut
uashtessiun uashtessiunipan
the colours change (in fall) the colours changed (in fall) the colours aren’t changing (in fall)

related topics
Verb Stems Roots, stems and inflections
Verb Classes Verb conjugations