Unusually, for gradation purposes nominals of this type act as if there was a consonant after the final -e of the nominative singular, as in vieras; thus the base form is weak. Historically, the stem ended in *-ek or *-eh, but the consonant was regularly lost word-finally. The inflectional stem added a linking -e- to the base form, leaving the root in its strong form, and gradated between -eke- (strong, as in essive *-ekenA) and -ee- (weak, as in most other cases). The inflectional stem was eventually levelled in favour of the weak form -ee-, resulting in all cases other than the nominative and partitive singular having an inflectional stem consisting the strong form of the root + -ee-. For details, see reconstructed Proto-Finnic *-ek.