Formation of the Perfect Stem.

[118]. The Perfect Stem is formed from the Verb Stem—

1. By adding v (in case of Vowel Stems); as,—

amāv-ī, dēlēv-ī, audīv-ī.

2. By adding u (in case of some Consonant Stems); as,—

strepu-ī, genu-ī, alu-ī.

3. By adding s (in case of most Consonant Stems); as,—

carp-ō, Perfect carps-ī.
scrīb-ō, " scrīps-ī (for scrīb-sī).
rīd-eō, " rīs-ī (for rīd-sī).
sent-iō, " sēns-ī (for sent-sī).
dīc-ō, " dīx-ī (i.e. dīc-sī).

a. Note that before the ending -sī a Dental Mute (t, d) is lost; a Guttural Mute (c, g) unites with s to form x; while the Labial b is changed to p.

4. Without addition. Of this formation there are three types:—