Traditionally, the Old Church Slavonic verb is considered to be capable of forming three types of aorist. The so-called root aorist is presumably formed by adding personal endings directly to the stem (Diels §114.1), as in the forms of the verb ‘to fall with the basic stem in pad- : 1st sg.
2d and 3d sg. pade, 1st du. padově, 2d du. padeta, 3d du. padete, 1st pl.
2d pl. padete, 3d pl.
The so-called s-aorist (Diels §114.2) is presumably formed by adding the element s (which under certain conditions alternates with x) directly to the stem, as in the respective forms of ved- ‘lead’ and rek- ‘speak’:
, vede, věsově, věsta, věste,
, věste,
, and
, reče, rěxově, rěsta, rěste,
, rěste,
. The so-called x-aorist (Diels §114.3) is formed by adding the element ox, as in the x-aorist forms of ved- :
, vede, vedoxově, vedosta, vedoste,
, vedoste, and
. In addition to automatic changes (such as x to š before a front vowel), it must be noted that the second and third persons singular are always formed on the root-aorist pattern; and that the third person plural ends in
in the root aorist but in
in the s- and x-aorists, as in the forms
(root aor.),
(s-aor.), and
(x-aor.). The distribution of the various types of aorist among stem classes is the following: class 1.1 (cf. Diels §105–6) has all three types in stems that end in an obstruent, as in the forms
and
stems of class 1.1 that end in a sonorant take s-aorist only; stems of class 2.1 take either the root aorist or the s-aorist; stems of class 2.2 and 3–6 take the s-aorist; and stems of class 7 (irregular) require individual disposition.