The 4th Principal Part
The fourth principal part, as the perfect passive participle, is an adjective. Usually just the masculine nominative singular is given. The complete forms are: -us, -a, -um. N.B.: intransitive verbs do not have a regular 4th principal part (because they can’t be made passive); this includes the verbs that take a dative (noceō, pāreō, etc.) Some are listed as –tum/-sum, which is the supine. Some have forms in -tūrus/-sūrus (e.g. sum – futūrus; veniō – ventūrus; fugiō – fugitūrus), which is the future active participle Some have no fourth form: (e.g. timeō – –; noceō —) See also the Dictionary Tips on various ways of giving the fourth principal part. For more on Principal Parts. Deponent or semi-deponent verbs have only three principal parts (with -tus/-sus sum for the third). They do not have a perfect active stem (corresponding to the third principal part) There are two basic types, those in -t- and those in -s-.Basic Regular Patterns by Conjugation
ā stem (1st Conjugation) amō, amāre, amāvī, amātus (-a, -um) deponent: arbitror, arbitrārī, arbitrātus (-a, -um) sum (Group 10) mīror, mīrārī, mīrātus (-a, -um) sum (Group 10) for, farī, fatus sum conor, conarī, conatus sum (moror, precor, versor, hortor) ē stem (2nd Conjugation) habeō, habēre, habuī, habitus (-a, -um) deponent: vereor, vererī, veritus (-a, -um) sum (3rd Conjugation) -ō, -ere, -ī, -tus/-sus (-a, -um) (regular: no vowel before -t/-s) dūcō, dūcere, dūxī, ductus 3rd -iō: -iō, -ere, -ī, -tus/-sus (regular: no vowel before -t/-s) capiō, capere, cēpī, captus -ī stem (4th Conjugation) audiō, audīre, audīvī, audītus (-a, -um)I. -tus, -a, -um
Regular (see also first page on Principal Parts) -ā stem (1st conjugation): -ātus (-a, -um) amō, amāre, amāvī, amātus (-a, -um) (Group 1) dō, dare, dedī, datus (Group 1) for compounds of dō, see 3rd conjugation in –tus stō, stāre, stetī, status (Group 5) constō, constāre, constitī, constātūrus (Group 12) (for the vowel weakening: -stet- > -stit, see Linguistic Rules #13) resistō, resistere, restitī (Group 16) -ē stem (2nd conjugation): -itus (-a, -um) habeō, habēre, habuī, habitus (-a, -um) (Group 1) Note: a few drop the vowel before the –tus: teneō contineō, continēre, continuī, contentum ( Group 15) sustineō, sustinēre. sustinuī, sustentum (Group 15) retineō, retinēre, retinuī, retentum (Group 8) pertineō, pertinēre, pertinuī, pertentum (Group 15) obtineō, obtinēre, obtinuī, obtentum (Group 15) doceō, docēre, docuī, doctus (Group 5) A few keep the –e- (instead of –i-): impleō, implēre, implēvī, implētus (-a, -um)(Group 9) compleō, complēre, complēvī, complētus (-a, -um)(Group 11) fleō, flēre, flēvī, flētus (-a, -um) (Group 9) [dēleō, dēlēre, dēlēvī, dēlētum] Contracted 1st/2nd iuvō, iuvāre, iūvī, iūtus (< iuvātus)(Group 7) moveō, movēre, mōvī, mōtus (for movitus)(Group 2) removeō, removēre, remōvī, remōtus (Group 15) caveō, cavere, cāvī, cautus (-a, -um) (Group 15) voveō, vovēre, vōvī, vōtus (Group 15) tueor, tuērī, tūtus sum Consonant stem (3rd conjugation) and 3rd iō: -tus (/sus) (-a, -um) Note: no vowel usually (added) before the -t. (see also Linguistic Rules #7-8) colo, colere, coluī, cultus (Group 8) deserō, desere, deseruī, desertus (Group 11) consulō, consulere, consuluī, consultus (Group 13) alō, alere, aluī, al(i)tus (Group 16) dīcō, dīcere, dīxī, dictus (Group 3) dūcō, dūcere, dūxī, ductus (Group 4) dēdūcō, dēdūcere, dēdūxī, dēductus (Group 14) addūcō, addūcere, addūcī, adductus (Group 11) redūcō, redūcere, redūxī, reductus (Group 8) ēdūcō, ēdūcere, ēdūxī, ēductus (Group 13) gerō (< ges-ō, see Linguistic Rules #2), gerere, gessī, gestus (Group 6) canō, canere, cecinī, cantus (Group 6) statuō, statuere, statuī, statūtus (Group 8) instituō, instituere, instituī, institūtus (Group 14) cōnstituō, cōnstituere, cōnstituī, cōnstitūtus (Group 8) induō, induere, induī, indūtus (Group 16) rapiō, rapere, rapuī, raptus (Group 13) ēripiō, ēripere, ēripuī, ēreptus (Group 13) [speciō, specere, spēxī, spectus] [spectō, spectāre, spectāvī, spectātus – frequentative] respiciō, respicere, respēxī, respectus (Group 13) aspiciō, aspicere, aspēxī, aspectus (Group 13) conspiciō, conspicere, conspēxī, conspectus (Group 13) faciō, facere, fēcī, factum (Group 2) interficiō, interficere, interfēcī, interfectum (Group 13) conficiō, conficere, confēcī, confectum (Group 11) dēficiō, dēficere, dēfēcī, dēfectum (Group 13) efficiō, efficere, effēcī, effectum (Group 13) perficiō, perficere, perfēcī, perfectum (Group 15) praeficiō, praeficere, praefēcī, praefectum (Group 12) iaciō, iacere, iēcī, iactus (Group 16) cōniciō, cōnicere, cōniēcī, coniectum (Group 16) capiō, capere, cēpī, captum (Group 1) incipiō, incipere, incēpī, inceptum (Group 13) accipiō, accipere, accēpī, acceptum (Group 2) recipiō, recipere, recēpī, receptum (Group 4) praecipiō, praecipere, praecēpī, praeceptum (Group 12) suscipiō, suscipere, suscēpī, susceptum (Group 13; 15; 16) excipiō, excipere, excēpī, exceptum (Group 13) pariō, parere, peperī, partus (Group 13) with -i- (-itus): bibō, bibere, bibī, bibitum (Group 8) (for dō see 1st conjugation) crēdō, crēdere, crēdidī, crēditus (Group 4) reddō, reddere, reddidī, redditus (Group 8) trādō, trādere, trādidī, traditus (Group 16) condō, condere, condidī, conditus (Group 14) perdō, perdere, perdidī, perditus (Group 11) addō, addere, addidī, additus (Group 14) prōdō, prodere, prodidī, proditus (Group 16) alō, alere, aluī, al(i)tus (Group 16) fugiō, fugere, fūgī, fugitūrus (Group 2) pōnō ( < posnō < posino), pōnere, posuī, positus (Group 4) impōnō, impōnere, imposuī, impositus (Groups 9 and 11) compōnō, compōnere, composuī, compositus (Group 11) prōpōnō, prōpōnere, prōposuī, prōpositus (Group 14) peto, petere, petīvī, petītus (Group 6) repeto, repetere, repetīvī, repetītus (Group 8) cupio, cupere, cupīvī, cupītus (Group 13) Vocalic “u” instead of consonantal “v” solvō, solvere, solvī (/soluī), solūtus (-a, -um) (Group 8) sternō, sternere, strāvī, strātus (Group 16)(with metathesis) volvō, volvere, volvī, volūtus (Group 14) sequor, sequī, secūtus (Group 6) consequor, consequī, consecūtus (Group 10) loquor, loquī, locūtus (Group 6) Voiced g-> unvoiced c before unvoiced t augeō, augēre, auxī, auctus (Group 15) regō, regere, rēxī, rēctus (Group 3) dīligō, dīligere, dīlēxī, dīlēctus (Group 6) tegō, tegere, tēxī, tēctus (Group 6) [legō, legere] intellegō, intellegere, intellexi, intellectus (Group 8) neglegō, neglegere, neglexī, neglectus (Group 14) vīvō, vivere, vīxī, vīctūrus (Group 1) (*g) trahō (trag-), trahere, traxī, tractus (Group 8) vehō, vehere, vēxī, vēctus (Group 14) (*g) cingō, cingere, cinxī, cinctus (Group 16) agō, agere, ēgī, āctus (Group 4) cōgō, cōgere, coēgī, coāctus (Group 11) frangō, frangere, frēgī, frāctus (Group 11) tangō, tangere, tetīgī, tāctus (Group 9) contingō, contingere, contigī, contāctus (Group 14) Voiced b-> unvoiced p before unvoiced t scrībō, scrībere, scrīpsī, scrīptus (Group 5) Miscellaneous -tus torqueō, torquēre, torsī, tortus (-a, -um) (Group 15) īnstruō, īnstruere, īnstrūxī, īnstrūctus (Group 16) sumō, sumere, sūmpsī, sūmptus (Group 11) (compare Spanish) contemnō, contemnere, contempsī, contemptus (Group 16) (compare Spanish) contendō, contendere, contendī, contentus (Group 16) ostendō, ostendere, ostendī, ostentus (Group 13) tendō, tendere, tetendī, tentus (Group 13) with loss of nasal infix vincō, vincere, vīcī, victus (Group 4) linquō, linquere, līquī, lictus (Group 14) relinquō, relinquere, relīquī, relictus (Group 3) rumpō, rumpere, rūpī, ruptus (Group 14) Inceptives (-scō suffix in present) nōscō, nōscere, nōvī, nōtus (Group 5) cōgnōscō, cognōscere, cōgnōvī, cōgnitus (Group 5) quiēscō, quiēscere, quiēvī, quiētus (Group 10) crescō, crescere, crēvī, crētum (Group 10) consuescō, consuescere, consuēvī, consuētus (Group 10) agnoscō, agnoscere, agnōvī, agnitus (Group 10) nascor, nascī, nātus sum (Group 6) proficiscor, proficiscī, profectus sum (Group 10) īrascor, īrascī, īrātus sum (Group 10) 4th with no –ī-: veniō, venīre, vēnī, ventūrus/ventum (Group 2) inveniō, invenīre, invēnī, inventus (Group 3) conveniō, convenīre, convēnī, conventus (Group 11) perveniō, pervenīre, pervēnī, perventus (Group 15) aperiō, aperīre, aperuī, apertus (Group 15) reperiō, reperīre, repperī, repertus (Group 15) orior, orīrī, ortus sum (Group 10) experior, experīrī, expertus sum (Group 10)II. -sus, -a, -um
Note: Most of these are stems in -d or -t. For 3rd conjugation: There is no vowel usually (added) before the -s. (see also Linguistic Rules #7-8) From stem in –t: sentiō, sentīre, sēnsī, sēnsus (Group 7) vertō, vertere, vertī, versus (Group 8) revertō, revertere, revertī, reversus (Group 8) convertō, convertere, convertī, conversus (Group 16) āvertō, āvertere, āvertī, āversus (Group 16) ūtor, ūtī, ūsus sum (Group 10) g+s or ct+s = x (See Linguistic Rules #3-4) flectō, flectere, flēxī, flexus (Group 16) complector, complectī, complexus sum (Group 10) fīgō, fīgere, fīxī, fixus (Group 16) From stem in –t with –ssus (by assimilation): mittō, mittere, mīsī, missus (Group 1) committō, committere, commīsī, commissus (Group 14) permittō, permittere, permīsī, permissus (Group 11) dīmittō, dīmittere, dīmīsī, dīmissus (Group 8) āmittō, āmittere, āmīsī, āmissus (Group 16) prōmittō, prōmittere, prōmīsī, prōmissus (Group 14) remittō, remittere, remīsī, remissus (Group 8) patior, patī, passus sum (Group 10) confiteor, confitērī, confessus sum (Group 10) From stem in –d: (usually with compenstory lengthening of the preceding vowel) videō, vidēre, vīdī, vīsus (Group 1) invideō, invidēre, invīdī, invīsus (Group 9) respondeō, respondēre, respondī, responsus (Group 1) audeō, audēre, ausus sum (semi-deponent)(Group 9) gaudeō, gaudēre, gāvisus sum (semi-deponent) (Group 9) ardeō, ardēre, arsī, arsum (Group 9) rīdeō, rīdēre, rīsī, rīsus (-a, -um)(Group 9) claudō, claudere, clausī, clausus (Group 14) dīvidō, dīvidere, dīvīsī, dīvīsus (Group 14) ēvādō, ēvādere, ēvāsī, ēvāsus (Group 13) lūdō, lūdere, lūsī, lūsus (Group 16) edō, edere/esse, ēdī, ēsus (Group 16) fundō, fundere, fūdī, fūsus (Group 13) (for the dropping of the nasal infix see Principal Parts) effundō, effundere, effūdī, effūsus (Group 13) cadō, cadere, cecidī, cāsūrus (Group 11) pendō, pendere, pependī, pēnsus (Group 16) defendō, defendere, defendī, defensus (Group 11) pandō, pandere, pandī, pansus/passus (Group 14) intendō, intendere, intendī, intentus/intensus (Group 9) [scandō, scandere] dēscendō, descendere, dēscendī, dēscēnsus (Group 14) ascendō, ascendere, ascendī, ascēnsus (Group 14) incendō, incendere, incendī, incensus (Group 16) occīdō, occīdere, occīdī, occīsus (< caedō) (Group 14) videor, vidērī, vīsus sum (Group 10)[persuadeō, persuādere, persuāsī, persuāsum] From stem in –d with –ssus (by assimilation): iubeō, iubēre, iussī, iussus (-a, -um)(Group 5) (*dh) sedeō, sedēre, sēdī, sessum (Group 9) cēdō, cēdere, cessī, cessus (-a, -um) (Group 8) dis-cēdō, dis-cēdere, dis-cessī, dis-cessus (Group 8) accēdō, accēdere, accessī, accessus (Group 8) concēdō, concēdere, concessī, concessus (Group 8) recēdō, recēdere, recessī, recessus (Group 8) procēdō, procēdere, processī, processus (Group 14) ingredior, ingredī, ingressus sum (Group 10) ēgredior, ēgredī, ēgressus sum (Group 10) -s other currō, currere, cucurrī, cursūrus (Group 11) premō, premere, pressī, pressus (Group 8) opprimō, opprimere, oppressī, oppressus (Group 8) fallō, fallere, fefellī, falsus (Group 8) pellō, pellere, pepulī, pulsus (Group 14) (Possible dental stem) impellō, impellere, impulī, impulsus (Group 14) lābor, lābī, lapsus sum (Group 10) -sum by analogy with perfect active parcō, parcere, pepercī(/parsī), parsūrus (Group 14) fluō, fluere, fluxī, fluxum (Group 11) *maneō, manēre, mānsī, mānsūrus (Group 9) remaneō, remanēre, remānsī, remānsūrus (Group 9) spargō, spargere, sparsī, sparsus (Group 14) -x other s-stem (rhotacized in present; See Linguistic Rules #2) haereō, haerēre, haesī, haesūrus (-a, -um)(Group 15) queror, querī, questus sum (Group 10)