2. After the analogy of Participles like sēnsus and caesus, where -sus arises by phonetic change, -sus for -tus is added to other Verb Stems; as,—

lāb-ī, Participle lāp-sus.
fīg-ere, " fī-xus.

a. The same consonant changes occur in appending this ending -sus to the stem as in the case of the Perfect ending -si (see [§ 118], 3, a).

3. A few Verbs form the Participle in -ĭtus; as,—

domā-re, dom-ĭtus.
monē-re, mon-ĭtus.

4. The Future Active Participle is usually identical in its stem with the Perfect Passive Participle; as, amā-tus, amātūrus; moni-tus, monitūrus. But—

juvā-re, Perf. Partic. jūtus, has Fut. Act. Partic. juvātūrus.[[40]]
lavā-re, " lautus, " lavātūrus.
par-ere, " partus, " paritūrus.
ru-ere, " rutus, " ruitūrus.
secă-re, " sectus, " secātūrus.
fru-ĭ, " frūctus, " fruitūrus.
mor-ī, " mortuus, " moritūrus.
orī-rī, " ortus, " oritūrus.

LIST OF THE MOST IMPORTANT VERBS, WITH PRINCIPAL PARTS.

First (Ā-) Conjugation.