The Present Stem
Ablaut in Present Stems
Present stem is formed from a verb stem with either a zero- or lengthened-grade ablaut:
- zero-grade: causative, derivative, formative (b) verbs;
- lengthened-grade: basic verbs, a-verbs, u-verbs, and formative (a) verbs.
Thematic and Athematic Presents
Forms built on the present stem follow either a thematic or an athematic conjugation.
- thematic conjugation: derivative and causative verbs.
- athematic conjugation: all other verbs.
Tense Endings
Tense endings are added after a theme vowel in thematic conjugations, or directly to stem in athematic conjugations.
- present tense endings: -yain derivative, causative verbs, and formative verbs;-ain other verbs;
- imperfect tense ending: -anein all conjugations;
Overview of Regular Forms
Examples (lengthened-grade ablaut stems and thematic vowels are highlighted):
| verb stem | present tense stem | imperfect tense stem | |
|---|---|---|---|
| basic | cen- | cén-a | cén-ane | 
| vocalic u | lir-u- | lír-u-a | lír-u-ane > líruáne | 
| long | talat- | talat-a | talat-ane > talatáne | 
| formative (a) | sir-y- | sír-y-ya > síria | sír-y-ane > síriáne | 
| formative (b) | is-t- | ís-t-ya > istya | ís-t-ane > istane | 
| vocalic a | far-a- | fár-a | fár-ane | 
| derivative | tengu-a- | tengu-a-ya > tenguea | tengu-a-ane > tenguáne | 
| causative (a) | tul-ya- | tul-y-a-ya > tulyea | tul-y-a-ane > tulyáne | 
| causative (b) | tul-ta- | tul-t-a-ya > tultea | tul-t-a-ane > tultáne | 
Particular Formations
Verbs Defective in Present
Verbs ending in -e(ng)a are defective and use their aorist tense form for present: te(ng)a- > tea shows, is showing.