Romance_verbs
Romance verbs are the most inflected part of speech in the language family. In the transition from Latin to the Romance languages, verbs went through many phonological, syntactic, and semantic changes. Most of the distinctions present in classical Latin continued to be made, but synthetic forms were often replaced with more analytic ones. Other verb forms changed meaning, and new forms also appeared.
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The following tables present a comparison of the conjugation of the regular verb amare "to love" in Classical Latin, and Vulgar Latin (reconstructed as Proto-Italo-Western Romance, with stress marked), and nine modern Romance languages. The conjugations below were given from their respective Wiktionary pages.
Because the verb "to love" in Romanian is iubi, of which goes back to Proto-Slavic origin and it is in 4th conjugation; while in Romansh is avair gugent which composed from the irregular verb avair, the conjugations in Romanian and Romansh only give the endings.
| Form | Classical Latin | Vulgar Latin | Major languages | Minor languages | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Spanish | Portuguese | Italian | French | Romanian | Sardinian (Logudorese) |
Sicilian | Catalan | Romansh | ||||||
| Infinitive | amāre | *amáre | amar | amar | amare | aimer | (-a) | amare | amari | amar | (-ar) | |||
| Present participle[lower-alpha 1] | amandus | *amándo | amando | amando | amando | aimant | (-ând) | – | amannu | amant | (-ond) | |||
| amāns | *amánte | amante | amante | amante[lower-alpha 2] | – | – | amende | – | – | – | ||||
| Past participle | amātum | *amáto | amado | amado | amato | aimé | (-at) | amadu | amatu | amat | (-à) | |||
| Indicative | Present | amō amās amat amāmus amātis amant |
*ámo *ámas *ámat *amámos *amátes *ámant |
amo amas ama amamos amáis aman |
amo amas ama amamos amais amam |
amo ami ama amiamo amate amano |
aime aimes aime aimons aimez aiment |
(-∅) (-i) (-ă) (-ăm) (-ați) (-ă) |
amo amas amat amamus amades amant |
amu ami ama amamu amati àmanu, àmunu |
amo ames ama amem ameu amen |
(-∅) (-as) (-a) (-ain) (-ais) (-an) | ||
| Imperfect | amābam amābās amābat amābāmus amābātis amābant |
*amába *amábas *amábat *amábamos *amábates *amábant |
amaba amabas amaba amábamos amabais amaban |
amava amavas amava amávamos amáveis amavam |
amavo amavi amava amavamo amavate amavano |
aimais aimais aimait aimions aimiez aimaient |
(-am) (-ai) (-a) (-am) (-ați) (-au) |
amaia amaias amaiat amaiamus amaiades amaiant |
amava, amavu amavi amava amàvamu amàvavu amàvanu, amàvunu |
amava amaves amava amàvem amàveu amaven |
(-ava) (-avas) (-ava) (-avan) (-avas) (-avan) | |||
| Preterite | amāvī amāvistī amāvit amāvimus amāvistis amāvērunt |
*amái *amásti *amáut *amámos *amástes *amáront |
amé amaste amó amamos amasteis amaron |
amei amaste amou amámos amastes amaram |
amai amasti amò amammo amaste amarono |
aimai aimas aima aimâmes aimâtes aimèrent[lower-alpha 3] |
(-ai) (-ași) (-ă) (-arăm) (-arăți) (-ară) |
amesi amesti amesit amemus amezis ameint |
amai amasti amau, amò amammu, amamu amastivu amàrunu, amaru |
amí amares amà amàrem amàreu amaren |
– | |||
| Pluperfect | amāveram amāveras amāverat amāverāmus amāverātis amāverant |
*amára *amáras *amárat *amáramos *amárates *amárant |
amara amaras amara amáramos amarais amaran[lower-alpha 4] |
amara amaras amara amáramos amáreis amaram[lower-alpha 5] |
– | – | – | – | amirìa amirissi amirìa amirìamu amirìavu amirìanu[lower-alpha 6] |
– | – | |||
| Future[lower-alpha 7] | amābō amābis amābit amābimus amābitis amābunt |
– | amaré amarás amará amaremos amaréis amarán |
amarei amarás amará amaremos amareis amarão |
amerò amerai amerà ameremo amerete ameranno |
aimerai aimeras aimera aimerons aimerez aimeront |
– | – | amirò, amirogghiu amirai amirà amiremu amireti, amiriti amirannu |
amaré amaràs amarà amarem amareu amaran |
– | |||
| Future perfect | amāverō amāveris amāverit amāverimus amāveritis amāverint |
*amáre *amáres *amáret *amáremos *amáretes *amárent |
amare amares amare amáremos amareis amaren[lower-alpha 8][lower-alpha 9] |
amar amares amar amarmos amardes amarem[lower-alpha 8] |
– | – | – | – | – | – | – | |||
| Subjunctive | Present | amem amēs amet amēmus amētis ament |
*áme *ámes *ámet *amémos *amétes *áment |
ame ames ame amemos améis amen |
ame ames ame amemos ameis amem |
ami ami ami amiamo amiate amino |
aime aimes aime aimions aimiez aiment |
(-∅) (-i) (-e) (-ăm) (-ați) (-e) |
ame ames amet amemus amedes ament |
amu ami ama amamu amati àmanu, àmunu |
ami ami ama amem ameu amin |
(-ia) (-ias) (-ia) (-ian) (-ias) (-ian) | ||
| Perfect | amāverim amāveris amāverit amāverimus amāveritis amāverint |
– | – | – | – | – | – | – | – | – | – | |||
| Imperfect | amārem amārēs amāret amārēmus amārētis amārent |
*amáre *amáres *amáret *amáremos *amáretes *amárent |
– | amar amares amar amarmos amardes amarem[lower-alpha 10] |
– | – | – | amere ameres ameret ameremus amerezes amerent |
– | – | – | |||
| Pluperfect[lower-alpha 11] | amāvissem amāvissēs amāvisset amāvissēmus amāvissētis amāvissent |
*amásse *amásses *amásset *amássemos *amássetes *amássent |
amase amases amase amásemos amáseis amasen |
amasse amasses amasse amássemos amásseis amassem |
amassi amassi amasse amassimo amaste amassero |
aimasse aimasses aimât aimassions aimassiez aimassent[lower-alpha 9] |
(-asem) (-aseși) (-ase) (-aserăm) (-aserăți) (-aseră) |
– | amassi amassi amassi amàssimu amàssivu amàssiru |
amés amessis amés améssim améssiu amessin |
(-ass) (-asses) (-ass) (-assen) (-asses) (-assen) | |||
| Imperative[lower-alpha 12] | amā amāte |
*áma *amáte |
ama amad |
ama amai |
ama amate |
aime aimez |
(-ă) (-ați) |
ama amade |
ama amati |
ama ameu |
(-a) (-ai) | |||
- Fell into disuse in modern Portuguese, now found only in literary texts. Nowadays largely replaced by the compound forms tinha amado or havia amado (had loved).
- The future indicative tense of the modern languages does not derive from the Latin form (which tended to be confounded with the preterite due to sound changes in Vulgar Latin), but rather from an infinitive + habeō periphrasis (*amáre ábio), later reanalysed as a simple tense. The conditional tense was formed similarly from the imperfect of habeō.
- Reanalysed as a personal infinitive. See below.
Note that the Vulgar Latin reconstructions are believed to have regularized word stress within each tense (except the present and imperative tenses). Word-final ⟨e⟩ probably converged on /ə/. Many verb forms undergoes elisions, like the indicative pluperfect amāveram > *amára and the subjunctive imperfect amāvissem > *amásse.
The verb "to love" in Old French amer, the early form of modern French is rather irregular but still follows its regular sound changes, with having aim- in stressed forms (namely the singular and third person plural of indicative and subjunctive present tenses, and the second person singular imperative), and the stem changes again to ain- before -s and -t in subjunctive present. In Catalan, the verb amar has replaced by synonymous estimar, the former usually used only in poetic contexts.
In this section, "Vulgar Latin" is actually reconstructed as reconstructed Proto-Italo-Western Romance, most notably the shift from Classical Latin -i- and -u- to -e- /e/ and -o- /o/, as opposed to inherited /ɛ/ and /ɔ/ respectively. The developments include:
- The -v- of the perfect tenses were dropped or elided, but sometimes become /u/ after vowels.
- The past participle were sometimes sporadically rounded to *-ū-, this situation is preserved in French.
- The "unstressed" indicative imperfect is very likely from shortened *-bămus, *-bătis, yielding to the stress on the third-from-last syllable (amābāmus), as opposed to Classical Latin stress on the second-from-last syllable (amābāmus). Languages which retains this irregular stress were the languages of Iberia, Sicilian, and French.
- Romance metaphony. In forms containing -ī next to mid-open vowels, especially in preterite forms were heightened.
In the Proto-Romance grammatical tradition, the second and third conjugation are known as third conjugation, similarly to French.
First conjugation
Verbs in the first conjugation are in -āre (*-áre), later evolved to -are in Italian, -ar in most Romance languages and -er in French.
| Infinitive | *-áre | ||||||
|---|---|---|---|---|---|---|---|
| Present participle | *-ánte | ||||||
| Gerund | *-ándo | ||||||
| Supine | *-áto | ||||||
| 1st singular | 2nd singular | 3rd singular | 1st plural | 2nd plural | 3rd plural | ||
| Indicative | Present | *-o[lower-alpha 1] | *-as[lower-alpha 1] | *-at[lower-alpha 1] | *-ámos | *-átes | *-ant[lower-alpha 1] |
| Imperfect | *-ába | *-ábas | *-ábat | *-ábamos | *-ábates | *-ábant | |
| Preterite | *-áui | *-áusti | *-áut | *-ámos | *-ástes | *-áront | |
| Pluperfect | *-ára | *-áras | *-árat | *-áramos | *-árates | *-árant | |
| Future perfect | *-áro | *-áres | *-áret | *-áremos | *-áretes | *-árent | |
| Subjunctive | Present | *-e[lower-alpha 1] | *-es[lower-alpha 1] | *-et[lower-alpha 1] | *-émos | *-étes | *-ent[lower-alpha 1] |
| Imperfect | *-áre | *-áres | *-áret | *-arémos | *-arétes | *-árent | |
| Pluperfect | *-ásse | *-ásses | *-ásset | *-assémos | *-assétes | *-ássent | |
| Imperative | *-a[lower-alpha 1] | *-áte | |||||
Second conjugation
Verbs in the second conjugation are in -ēre (*-ére), later evolved to -ere in Italian, -er in most Romance languages and -oir in French (no "regular" -oir verbs). Another infinitive -ere has merged into this paradigm.
| Infinitive | *-ére | ||||||
|---|---|---|---|---|---|---|---|
| Present participle | *-énte | ||||||
| Gerund | *-éndo | ||||||
| Supine | *-eto[lower-alpha 1] | ||||||
| 1st singular | 2nd singular | 3rd singular | 1st plural | 2nd plural | 3rd plural | ||
| Indicative | Present | *-io[lower-alpha 1] | *-es[lower-alpha 1] | *-et[lower-alpha 1] | *-émos | *-étes | *-ent[lower-alpha 1] |
| Imperfect | *-éba | *-ébas | *-ébat | *-ébamos | *-ébates | *-ébant | |
| Preterite | *-í | *-ísti | *-ét | *-émos | *-éstes | *-éront | |
| Pluperfect | *-éra | *-éras | *-érat | *-éramos | *-érates | *-érant | |
| Future perfect | *-éro | *-éres | *-éret | *-éremos | *-éretes | *-érent | |
| Subjunctive | Present | *-ia[lower-alpha 1] | *-ias[lower-alpha 1] | *-iat[lower-alpha 1] | *-iámos | *-iátes | *-iant[lower-alpha 1] |
| Imperfect | *-ére | *-éres | *-éret | *-éremos | *-éretes | *-érent | |
| Pluperfect | *-ésse | *-ésses | *-ésset | *-essémos | *-essétes | *-éssent | |
| Imperative | *-é[lower-alpha 1] | *-éte | |||||
Third conjugation
Verbs in the third conjugation are in -ere (*-ere, caused stress in previous syllable), later merged with -ere (*-ere, causes stress in antepenultimate syllable), but -re in French and Catalan. The suffix -re in French are in the third group, also known as irregular verbs.
The -iō variant (*-io in Vulgar Latin) now defunct, later merged with the second conjugation; the paradigm now only exists in some descendants of the verb faciō.
| Infinitive | *-ere[lower-alpha 1] | ||||||
|---|---|---|---|---|---|---|---|
| Present participle | *-énte | ||||||
| Gerund | *-éndo | ||||||
| Supine | *-eto[lower-alpha 1] | ||||||
| 1st singular | 2nd singular | 3rd singular | 1st plural | 2nd plural | 3rd plural | ||
| Indicative | Present | *-o[lower-alpha 1] | *-es[lower-alpha 1] | *-et[lower-alpha 1] | *-émos | *-étes | *-ont[lower-alpha 1] |
| Imperfect | *-éba | *-ébas | *-ébat | *-ébamos | *-ébates | *-ébant | |
| Preterite | *-í | *-ísti | *-ét | *-émos | *-éstes | *-érent | |
| Pluperfect | *-éra | *-éras | *-érat | *-éramos | *-érates | *-érant | |
| Future perfect | *-éro | *-éres | *-éret | *-éremos | *-éretes | *-érent | |
| Subjunctive | Present | *-a[lower-alpha 1] | *-as[lower-alpha 1] | *-at[lower-alpha 1] | *-ámos | *-átes | *-ant[lower-alpha 1] |
| Imperfect | *-ére | *-éres | *-éret | *-éremos | *-éretes | *-érent | |
| Pluperfect | *-ésse | *-ésses | *-ésset | *-essémos | *-essétes | *-éssent | |
| Imperative | *-e[lower-alpha 1] | *-éte | |||||
Fourth conjugation
Verbs in the fourth conjugation are in -īre (*-íre), later evolved to -ire in Italian, and -ir in most Romance languages. This conjugation type are infixed with once-inchoative -īsc- → *-ísc- in some languages, but its placement varies.
| Infinitive | *-íre | ||||||
|---|---|---|---|---|---|---|---|
| Present participle | *-iénte | ||||||
| Gerund | *-iéndo | ||||||
| Supine | *-íto | ||||||
| 1st singular | 2nd singular | 3rd singular | 1st plural | 2nd plural | 3rd plural | ||
| Indicative | Present | *-io[lower-alpha 1] | *-is[lower-alpha 1] | *-it[lower-alpha 1] | *-ímos | *-ítes | *-iont[lower-alpha 1] |
| Imperfect | *-iéba | *-iébas | *-iébat | *-iébamos | *-iébates | *-iébant | |
| Preterite | *-i | *-ísti | *-it | *-ímos | *-ístes | *-íront | |
| Pluperfect | *-íra | *-íras | *-írat | *-íramos | *-írates | *-írant | |
| Future perfect | *-íro | *-íres | *-íret | *-íremos | *-íretes | *-írent | |
| Subjunctive | Present | *-ia[lower-alpha 1] | *-ias[lower-alpha 1] | *-iat[lower-alpha 1] | *-iamos | *-iates | *-iant[lower-alpha 1] |
| Imperfect | *-íre | *-íres | *-íret | *-íremos | *-íretes | *-írent | |
| Pluperfect | *-ísse | *-ísses | *-ísset | *-íssemos | *-íssetes | *-íssent | |
| Imperative | *-i[lower-alpha 1] | *-íte | |||||
In Italian, Catalan, and Romanian, the infix -isc-; -esc-, -eix- (Catalan), and -ăsc- (Romanian) is placed on once-stressed indicative and subjunctive present forms (the first-, second-, third-singular and third plural present tenses), and stressed imperatives. In French, the infix -iss- is placed on all indicative present forms, the indicative imperfect, the subjunctive present, and plural imperatives.
While there are few non-infixed -īre verbs (also known are pure -īre verbs), in French the infixed verbs are the only regular verbs, otherwise irregular.
While the nominal morphology in Romance languages is primarily agglutinative, the verbal morphology is fusional. The verbs are highly inflected for numbers (singular and plural), persons (first-, second-, and third-person), moods (indicative, conditional, subjunctive, and imperative), tenses (present, past, future), and aspects (imperfective and perfective).
Because of the complexities in Romance conjugation, certain languages have a separate article regarding these conjugations:
- Italian conjugation
- Spanish verbs
- Portuguese verb conjugation
- Romanian verbs
- French conjugation
- Catalan verbs
- Occitan conjugation
- Sardinian conjugation
While there are 4 regular infinitives in Classical Latin, namely -āre, -ēre, -ere, and -īre, some of these infinitive were merged. In many Romance languages including Spanish and Portuguese, the main infinitives are -ar, -er, and -ir, with addition of -ôr (Portuguese only) which only exists in the verb pôr, traditionally considered as -er verbs. While in Italian, the infinitives are -are, -ere, -ire. The infinitives -er and -ere (Italian) resulted from the merge of Latin infinitives -ēre and -ere. In French, the infinitives are -er, -oir, -re, -ir, but verbs with -oir and -re are in the third group, also known as irregular verbs.
Latin deponent verbs like sequor and nascor (infinitive sequī, nascī) changed to active counterparts *séquo and *násco (infinitive *séquere, *nascere), as in Portuguese seguir, Spanish seguir, and Italian seguire; and Portuguese nascer, Spanish nacer, and French naître.
| Hard | Soft | ||
|---|---|---|---|
| Back vowels | Front vowels | Back vowels | Front vowels |
| c- | quV- | z- | c- |
| g- | guV- | j- | g- |
In many Romance languages, verb stems ending in -c, -z shown above were regularly altered to preserve its pronunciation. However, it is not considered irregular.
True irregular verbs
Copula
While the passive voice became completely periphrastic in Romance, the active voice has been morphologically preserved to a greater or lesser extent. The tables below compare the conjugation of the Latin verbs sum and stō in the active voice with that of the Romance copulae, their descendants. For simplicity, only the first person singular is listed for finite forms. Note that certain forms in Romance languages come from the suppletive sources sedeo (to be seated) instead of sum, e.g. subjunctive present: sedea > sia, sea, seja... (medieval Galician-Portuguese, for instance, had double forms in the whole conjugation: sou/sejo, era/sia, fui/sevi, fora/severa, fosse/sevesse...)
| Form | Latin | Italian | French1 | Spanish | Portuguese | Logudorese | Catalan | Sicilian | Romansh | Romanian | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Indicative | Present | sum | stō | sono | sto | suis | – | soy | estoy | sou | estou | so | isto | sóc | estic | sugnu | staiu | sun | sunt | |
| Imperfect | eram | stābam | ero | stavo | – | étais | era | estaba | era | estava | essia | istaia | era | estava | era | stava | era | eram | ||
| Preterite | fuī | stetī | fui | stetti | fus | – | fui | estuve | fui | estive | essesi | istesi | fui | estiguí | fui | stesi | – | fui, fusei | ||
| Pluperfect | fueram | steteram | – | – | – | – | fuera | estuviera | fora | estivera | – | – | fóra | estigués | fora | – | – | – | ||
| Future2 | erō | stābō | sarò | starò | serai | – | seré | estaré | serei | estarei | – | – | seré | estaré | – | – | – | – | ||
| Subjunctive | Present | sim | stem | sia | stia | sois | – | sea | esté | seja | esteja | sia | iste | sigui, siga | estigui, estiga | – | – | saja | să fiu | |
| Perfect3 | fuerim | steterim | – | – | – | – | fuere | estuviere | for | estiver | – | – | – | – | – | – | – | – | ||
| Imperfect | essem | starem | – | – | – | – | – | – | ser | estar | essere | istere | – | – | – | – | – | – | ||
| Pluperfect | fuissem | stetissem | fossi | stessi | fusse | – | fuese | estuviese | fosse | estivesse | – | – | fos | estigués | fussi | stassi | fiss | fusesem | ||
| Infinitive | esse | stāre | essere | stare | être | – | ser | estar | ser | estar | essere | istare | ser, ésser | estar | siri | stari | esser | fire, a fi | ||
| Supine | – | statum | – | stato | – | été | sido | estado | sido | estado | essidu | istadu | estat, sigut, sét | estat | statu | statu | stà | fost | ||
| Gerund | – | standum | essendo | stando | – | étant | siendo | estando | sendo | estando | essende | istande | sent, essent | estant | sennu | stannu | essend, siond | fiind | ||
- In French the outcomes of sum and stō merged into a single verb paradigm; here the various forms are separated according to which root they descend from.
- The future indicative tense does not derive from the Latin form (which tended to be confounded with the preterite due to sound changes in Vulgar Latin), but rather from an infinitive + habeō periphrasis, later reanalysed as a simple tense.
- Formally identical to the future perfect indicative, the two paradigms merged in Vulgar Latin.
Other irregular verbs
- "To have": The verb habeō was regularly conjugated in Classical Latin, but later tends to be highly irregular in the Romance languages. The verb later transformed to *haveō in many Romance languages (but etymologically Spanish haber), resulting in irregular indicative present forms *ai, *as, and *at (all first-, second- and third-person singular), but ho, hai, ha in Italian and -pp- (appo) in Logudorese Sardinian in present tenses.
- In Logudorese Sardinian, two -b-es lost in imperfect tenses.
- In French, the past participle eu including the perfect stems (past historic and subjunctive imperfect stems) eu-/eû- rather evolved from earlier *habū-.
This is the Vulgar Latin conjugation of the verb *avére:
| Infinitive | *avére | ||||||
|---|---|---|---|---|---|---|---|
| Present participle | *avénte | ||||||
| Gerund | *avéndo | ||||||
| Supine | *áuto | ||||||
| 1st singular | 2nd singular | 3rd singular | 1st plural | 2nd plural | 3rd plural | ||
| Indicative | Present | *áio | *áus | *áut | *avémos | *avétes | *áunt |
| Imperfect | *avéba | *avébas | *avébat | *avébamos | *avébates | *avébant | |
| Preterite | *áui | *avésti | *áut | *avémos | *avéstes | *áuront | |
| Pluperfect | *avéra | *avéras | *avérat | *avéramos | *avérates | *avérant | |
| Future | *avére áio | *avére áus | *avére áut | *avére avémos | *avére avétes | *avére áunt | |
| Conditional | *avére avéba | *avére avéba | *avére avébat | *avére avébamos | *avére avébates | *avére avébant | |
| Future perfect | *avéro | *avéres | *avéret | *avéremos | *avéretes | *avérent | |
| Subjunctive | Present | *áia | *áias | *áiat | *aiámos | *aiátes | *áiant |
| Imperfect | *avére | *avéres | *avéret | *avéremos | *avéretes | *avérent | |
| Pluperfect | *avésse | *avésses | *avésset | *avessémos | *avessétes | *avéssent | |
| Imperative | *áu | *avéte | |||||
Notice that these forms sometimes also have an inconsistent form, as the table above more resembling with that of French.
- "To do": The verb faciō is also irregular in Classical Latin, with fēc- before perfect tenses (although the passive form of the verb was supplied by fīō, this suppletion is not included as the passive voice became periphrastic). This verb is one of the few verbs that retains perfect ablaut in Romance languages, with some changing the perfect stem to fi- due to metaphony rules.
In spite of the remarkable continuity of form, several Latin tenses have changed meaning, especially subjunctives.
- The verbal noun became a present participle in all Romance languages except in Italian and Romanian, where it became a gerund, and Sardinian, where it does not exist. However, the French and Catalan suffixes -ant conflate with the accusative of present active participle suffix -āntem.
- The supine became a past participle in all Romance languages.
- The pluperfect indicative became a conditional in Sicilian, and an imperfect subjunctive in Spanish.
- The pluperfect subjunctive developed into an imperfect subjunctive in all languages except Romansh, where it became a conditional, and Romanian, where it became a pluperfect indicative.
- The future perfect indicative became a future subjunctive in Old Spanish, Portuguese, and Galician.
The Latin imperfect subjunctive underwent a change in syntactic status, becoming a personal infinitive in Portuguese and Galician.[1] An alternative hypothesis traces the personal infinitive back to the Latin infinitive, not to a conjugated verb form.[2]
In many cases, the empty cells in the tables above exist as distinct compound verbs in the modern languages. Thus, the main tense and mood distinctions in classical Latin are still made in most modern Romance languages, though some are now expressed through compound rather than simple verbs. Some examples, from Romanian:
- Perfect indicative: am fost, ai fost, a fost, am fost, ați fost, au fost;
- Future indicative: voi fi, vei fi, va fi, vom fi, veți fi, vor fi;
- Future perfect indicative: voi fi fost, vei fi fost, va fi fost, vom fi fost, veți fi fost, vor fi fost.
New forms also developed, such as the conditional, which in most Romance languages started out as a periphrasis, but later became a simple tense. In Romanian, the conditional is still periphrastic: aș fi, ai fi, ar fi, am fi, ați fi, ar fi.
- Maurer, Theodoro H. (1968). O infinitivo flexionado português: estudo histórico-descritivo (in Portuguese). São Paulo: Companhia Editora Nacional.
- Paola Monachesi, The Verbal Complex in Romance: A Case Study in Grammatical Interfaces. Oxford: Oxford University Press, 2005.
- Osborne, Bruce (1982). "On the origin of the Portuguese inflected infinitive". In Anders Ahlqvist (ed.). Papers from the Fifth International Conference on Historical Linguistics, Galway, April 6–10, 1981. Amsterdam: John Benjamins Publishing Company. pp. 243–48. ISBN 978-90-272-3514-5.
- Williams, Edwin Bucher (1962). From Latin to Portuguese: Historical phonology and morphology of the Portuguese language (2nd ed.). Philadelphia: University of Pennsylvania Press.
- Wireback, Kenneth J. (1994). "The Origin of the Portuguese Inflected Infinitive". Hispania. 77 (3): 544–554. doi:10.2307/344992. JSTOR 344992.