For -stitī, see [860]. The compound prae-stō has rarely the perfect participle prae-stātus (Brut., Plin.), and prae-stitus (Liv.).
[990.] (2.) The following verbs in -āre have a perfect stem consisting of a root which ends in -v- and has a long vowel ([864]), and the perfect participle in -tus:
| iuvō, help | iuvāre | iūvī | iūtus once |
In the perfect system, iuverint, adiuverō, and adiuverit occur once each in Catull., Enn., Plaut., and Ter.; see [891]. Perfect participle usual only in the compound ad-iūtus.
| lavō, bathe | lavāre | lāvī | lautus |
Forms in -ere are very common in the present tense ([820]): lavis (Plaut., Hor.), lavit (Plaut., Lucr., Catull., Verg., Hor.), lavimus (Hor.), lavitur (Val. Fl.), lavitō (Cato), lavere often, lavī (Pomp.). Perfect participle often lōtus in writers of the empire; supine, lautum, lavātum.
[(B.) PERFECT STEM IN -v- OR -u-.]
PERFECT STEM IN -v-.
[991.] (1 a.) Two verbs in -āre have the perfect stem in -v- ([869]), and the perfect participle, when used, in -tus, both preceded by a long -ā- of the root:
| flō, blow | flāre | flāvī | flātus |
| nō, swim | nāre | nāvī | —— |