[866.] (3.) Some verbs in -ere from roots ending in two consonants have a perfect stem consisting of the root: as,

Perfect Stem.Verb.From Theme.
mand-mandō, chewmand-
pand-pandō, openpand-

Other examples are: vortō or vertō, turn, vortī or vertī; scandō, climb, -scendī; prehendō, seize, prehendī ([855]); vollō or vellō, pluck, vollī or vellī; see [949-951]. Similarly ferveō, boil, fervere or fervēre, has fervī or ferbuī ([823]), and prandeō, lunch, prandēre, has prandī.

(B.) PERFECT STEM IN -s-, OR IN -v- OR -u-.

PERFECT STEM IN -s-.

[867.] Many verbs in -ere form their perfect stem by adding the suffix -s- to a root, which generally ends in a mute: as,

Perfect Stem.Verb.From Theme.
carp-s-carpō, pluckcarp-
scalp-s-scalpō, digscalp-
ges-s-gerō, bearges-
dīx-dīcō, saydīc-

Other examples are: dūcō, lead, dūxī ([100]); fingō, mould, fīnxī ([855]); lūdō, play, lūsī ([166, 2]); scrībō, write, scrīpsī ([164, 1]); struō, pile, strūxī ([164, 1]); vīvō, live, vīxī ([98]). Some verbs with a short vowel in the present, have a long vowel in the perfect: as, regō, guide, rēxī ([135]); intellegō, understand, intellēxī ([823]); tegō, cover, tēxī; iungō, join, iūnxī ([855]). And some verbs with a long vowel in the present, have a short vowel in the perfect: as, ūrō, burn, ussī ([830]). See [952]-961.

[868.] Some verbs in -ēre also have a perfect in -s-: as algeō, am cold, alsī ([170, 3]); haereō, stick, haesī ([166, 2]): see [999], [1000]. Also some in -īre: as, sarciō, patch, sarsī ([170, 3]): see [1014], [1015].

PERFECT STEM IN -v- OR -u-.