Latin syntax

Latin syntax is the part of Latin grammar that covers such matters as word order, the use of cases, tenses and moods, and the construction of simple and compound sentences, also known as periods.
The study of Latin syntax in a systematic way was particularly a feature of the late 19th century, especially in Germany. For example, in the 3rd edition of Gildersleeve's Latin Grammar, the reviser, Gonzalez Lodge, mentions 38 scholars whose works have been used in its revision; of these 31 wrote in German, five in English and two in French..
In the twentieth century, the German tradition was continued with the publication of two very comprehensive grammars: the Ausführliche Grammatik der lateinischen Sprache by Raphael Kühner and Karl Stegmann, and the Lateinische Grammatik by Manu Leumann, J.B. Hofmann, and Anton Szantyr. Among works published in English may be mentioned E.C. Woodcock's A New Latin Syntax. More recently, taking advantage of computerised texts, three major works have been published on Latin word order, one by the American scholars Andrew Devine and Laurence Stephens, and two by the Czech scholar Olga Spevak.

Latin word order

Latin word order is relatively free. The verb may be found at the beginning, in the middle, or at the end of a sentence; an adjective may precede or follow its noun ; and a genitive may precede or follow its noun. There are also stylistic differences between Latin authors; for example, while Caesar always writes castra pōnit 'he sets up camp', Livy more often writes pōnit castra.
There are however certain constraints; for example, in prose a monosyllabic preposition such as in 'in' generally precedes its noun. Moreover, even though adjectives can both precede and follow the noun, there is a tendency for different kinds of adjectives to take different positions; for example adjectives of size usually come before the noun, while "modifiers that are more important than their noun or that specify it" usually follow it.
To explain Latin word order there are two main schools of thought. One, represented by Devine and Stephens, argues from the point of view of generative grammar, and maintains that Latin prose has a basic underlying "neutral" word order, from which authors deviate for reasons of emphasis, topicalisation, rhythm, and so on. According to Devine and Stephens, the basic order in broad scope focus sentences is as follows:

Subject – Direct Object – Indirect Object / Oblique Argument – Adjunct – Goal or Source Argument – Non-Referential Direct Object – Verb

The other approach, represented by Panhuis and Olga Spevak, examines Latin word order from the point of view of functional grammar. Rejecting the idea that there is a basic word order, this approach seeks to explain word order in terms of pragmatic factors, such as topic and focus, and semantic ones.

Examples of word order

The order of words is often chosen according to the emphasis required by the author. One way of emphasising a word is to reverse the usual order. For example, in the opening sentence of Caesar's Gallic War, the usual order of numeral and noun trīs partīs 'three parts' is reversed to emphasise the number "three":

Gallia est omnis dīvīsa in partes tres

Another technique used by Latin authors is to separate a phrase and put another word or phrase in the middle, for example:

magnam enim sēcum pecūniam portābat

The technical term for this kind of separation is "hyperbaton" ; it is described by Devine and Stephens as 'perhaps the most distinctively alien feature of Latin word order'.
Placing the verb at or near the beginning of a clause sometimes indicates that the action is sudden or unexpected:

statim complūrēs cum tēlīs in hunc faciunt dē locō superiōre impetum

Splitting up an adjective-noun phrase and bringing the adjective to the beginning of the sentence can highlight it. In the following example from Cicero, the splitting of cruentum 'blood-stained' and pugiōnem 'dagger' creates a dramatic effect:

statim cruentum altē tollēns Brūtus pugiōnem Cicerōnem nōminātim exclāmāvit

Considerations of rhythm and elegance also play a part in Latin word order. For example, Pliny the Younger begins a letter as follows:

magnum prōventum poētārum annus hic attulit

In this sentence, the object has been brought forward to highlight it. The other striking feature is the order annus hic for the more usual hic annus 'this year'. Two reasons which might be suggested are Pliny's fondness for ending a sentence with the rhythm − u − − u − and also no doubt because of the elegant assonance of the vowels a-u-i a-u-i in the last three words.

Gender and number

Gender and number agreement

Latin has three genders and two numbers. Pronouns, adjectives, participles, and the numbers one to three have to agree in gender and number with the noun they refer to:

Masculine : hic est fīlius meus: 'this is my son'
Feminine : haec est fīlia mea : 'this is my daughter'
Neuter : hoc est corpus meum: 'this is my body'

The same three genders are also found in the plural:

Masculine : hī sunt fīliī meī : 'these are my sons'
Feminine : hae sunt fīliae meae : 'these are my daughters'
Neuter : haec mea sunt: 'these things are mine'

In Latin, words referring to males are always masculine, words referring to females are usually feminine. Words referring to things can be any of the three genders, for example mōns 'mountain', arbor 'tree', nōmen 'name'. However, there are certain rules; for example, nouns with the suffixes -a, -tiō, -tās are feminine; the names of trees, islands, and countries, such as pīnus 'pine', Cyprus 'Cyprus', and Aegyptus 'Egypt' are also usually feminine, and so on. Some nouns such as parēns 'parent' can vary between masculine and feminine and are called of "common" gender.
When words of different genders are combined, the adjective is usually masculine if referring to people, neuter if referring to things:

patēr mihī et mātēr mortuī
mūrus et porta dē caelō tācta erant

However, sometimes the adjective may agree with the nearest noun.

Latin cases

Nouns, pronouns, and adjectives in Latin change their endings according to their function in the sentence. The different endings are called different "cases". Case endings of a similar kind are also found in other languages, such as Ancient and Modern Greek, German, Russian, Hungarian, Finnish, Sanskrit, Armenian, Classical Arabic, and Turkish.
The six cases most commonly used in Latin and their main meanings are given below. The cases are presented here in the order Nom, Voc, Acc, Gen, Dat, Abl, which has been used in Britain and countries influenced by Britain ever since the publication of Kennedy's Latin Primer in the 19th century. A different order – Nom, Gen, Dat, Acc, Voc, Abl, or its variation Nom, Gen, Dat, Acc, Abl, Voc – is used in many European countries and the United States.

Nominative : rēx : 'the/a king'
Vocative : rēx! : 'o king!'
Accusative : rēgem : 'the king'
Genitive : rēgis : 'of the king'
Dative : rēgī : 'to the king', 'for that king'
Ablative : rēge : 'with the king'

Another case is the locative, which is used mostly with the names of cities and a very limited number of ordinary nouns.

Examples of case use

The following examples from Caesar show the cases used in a basic sense:

Caesar ... mīlitibus signum dedit

Here Caesar is the subject of the sentence, and so nominative case; mīlitibus 'to the soldiers' is dative case, a case typically used with the verb dō 'I give' ; while signum is the direct object, and so accusative case.

Cūriō Mārcium Uticam nāvibus praemittit

Here Cūriō as subject of the verb is nominative, Mārcium as direct object is accusative; Uticam is also accusative as it is the goal or object of motion; and nāvibus 'with the ships' has the ablative ending. Although the ending -ibus is the same for both dative and ablative plural, the ablative meaning "with" is more appropriate in this context.

Pompeius ... Lūceriā proficīscitur Canusium

Here Pompeius is subject, Lūceriā shows another meaning of the ablative ending, namely 'from', and Canusium is again accusative of goal. With names of cities there is no need to add a preposition such as ad 'to', but the accusative case alone indicates "to".
An example illustrating the genitive case is the following:

ad castra Caesaris omnibus cōpiīs contendērunt

Here castra, the goal of motion, is in the accusative following the preposition ad 'to' or 'towards'; Caesaris 'of Caesar' or 'Caesar's' is in the genitive case; and omnibus cōpiīs 'with all their forces' is in the ablative case, with the meaning 'with'.

Idioms using the dative case

The description of the use of cases is not always straightforward. The classification of the uses of the dative alone takes up nearly twelve pages in Woodcock's A New Latin Syntax and ten pages in Gildersleeve and Lodge. For example, when asking someone's name, a Roman would say:

quid est tibī nōmen?

This is an example of the dative of possession, as in:

illī... duae fuēre fīliae

Another idiomatic use is the "dative of the person affected":

nihil equidem tibī abstulī

The dative is also used with verbs of fighting with someone:

nōlī pugnāre duōbus

Another idiom is the "predicative dative" used with the verb 'to be' in phrases such as ūsuī esse 'to be of use', labōrī esse 'to be a trouble ':

nēminī meus adventus labōrī aut sūmptuī... fuit

Many verbs which in English take a direct object are used in Latin intransitively with a dative noun or pronoun, e.g. persuādeō 'I persuade', crēdō 'I believe', resistō 'I resist'.

nōn persuāsit illī
imperāvit eī

Prepositions

Frequently, to make the meaning more precise, a noun in the accusative or ablative is preceded by a preposition such as in 'in, into', ad 'to', cum 'with', or ex 'out of'. This is especially so if the noun refers to a person. For example:

ad rēgem 'to the king'
ā rēge 'by the king', 'from the king'
cum eō 'with him'
ex urbe 'from/out of the city'

However, when the meaning of an accusative or an ablative is clear 'to Canusium', nāvibus 'with the ships', posterō diē, the case ending alone is sufficient to give the meaning. Unlike in Greek, prepositions are not used in Latin with the dative or genitive.

Prepositions with accusative or ablative

Four prepositions can be followed by more than one case, depending on their meaning. These are in 'in', 'into' ; sub 'under', 'to the foot of' ; super 'over, above', 'concerning' ; and subter 'under'

in urbem 'into the city'
in urbe 'in the city'

Position of prepositions

Prepositions almost always precede their noun or pronoun, except that cum 'with' follows a personal pronoun, e.g. mēcum 'with me' and sometimes a relative pronoun. There are occasional exceptions, especially with two-syllable prepositions after pronouns, e.g. haec inter 'in the midst of these'.
Sometimes when the noun has an adjective it is placed before the preposition for emphasis, e.g. magnā cum cūrā 'with great care', but this is not an invariable rule. Occasionally also the opposite order may be used in poetry and later prose, e.g. silvā lupus in Sabīnā 'a wolf in the Sabine forest', or metū in magnō 'in great fear'.

Latin tenses

Latin has six main tenses in the indicative mood, which are illustrated below using the verb facere 'to make' or 'to do':

Present : faciō : 'I do', 'I am doing'
Future : faciam : 'I will do', 'I will be doing'
Imperfect : faciēbam : 'I was doing', 'I used to do', 'I began to do'
Perfect : fēcī : 'I did', 'I have done'
Future Perfect : fēcerō : 'I will have done'
Pluperfect : fēceram : 'I had done'

The verb sum 'I am', which is irregular, has the tenses sum, erō, eram, fuī, fuerō, fueram. Some verbs instead of the Future -am, -ēs, -et etc. have a different future ending in -bō, -bis, -bit, e.g. amābō 'I will love'.
To these six ordinary tenses may be added various "periphrastic" tenses, made from a participle and part of the verb sum 'I am', such as factūrus eram 'I was about to do'.
For the most part these tenses are used in a fairly straightforward way; however, there are certain idiomatic uses that may be noted. Note in particular that the Latin perfect tense combines the English simple past with the present perfect into a single form; this can make the perfect verb "feel" like it is set in the present for the purpose of grammatical sequence of tenses.

Passive and deponent verbs

Passive and deponent tenses

In addition to the active voice tenses listed above, Latin has a set of passive voice tenses as follows:

Present : capior : 'I am captured', 'I am being captured'
Future : capiar : 'I will be captured'
Imperfect : capiēbar : 'I was being captured', 'I used to be captured'
Perfect : captus sum : 'I was captured', 'I have been captured'
Future Perfect : captus erō : 'I will have been captured'
Pluperfect : captus eram : 'I had been captured'

The three perfect tenses are formed using the perfect participle together with part of the verb sum 'I am'. The ending of the participle changes according to the gender and number of the subject: captus est 'he or it was captured'; capta est 'she or it was captured'; captī sunt 'they were captured', and so on.
Deponent verbs have exactly the same form as passive verbs except that the meaning is active, not passive:

Present : ingredior : 'I enter', 'I am entering'
Future : ingrediar : 'I will enter'
Imperfect : ingrediēbar : 'I was entering, 'I used to enter'
Perfect : ingressus sum : 'I entered', 'I have entered'
Future Perfect : ingressus erō : 'I will have entered'
Pluperfect : ingressus eram : 'I had entered'

The use of passive verbs

A passive verb is generally used when it is unnecessary to indicate who did the action:

sē hostibus obtulit atque interfectus est.

An intransitive verb can also be made passive, provided it is used impersonally in the neuter singular:

ubi ad rādīcēs montium... ventum est, signum extemplō datur

When it is desired to show the agent or person by whom the action was done, Latin uses the preposition ab or ā with the ablative case:

arx ab hostibus capta est

When the agent is not a person but a thing, no preposition is used, but simply the ablative case:

corripitur flammīs... tellūs

Passive of "give"

In Latin, unlike English, only the direct object of an active verb can be made the subject of a passive verb. It is not correct to say in Latin 'the soldiers were being given their pay' but only 'pay was being given to the soldiers':

''mīlitibus stīpendium ''

Impersonal passive

Another unusual feature of Latin, compared with English, is that intransitive verbs such as eō 'I go', veniō 'I come', pugnō 'I fight' and persuādeō 'I persuade' can be made passive, but only in a 3rd person singular impersonal form:

ītur in antīquam silvam
septimō diē Carthāginem ventum est
''persuāsum erat Cluviō ut mentīrētur''

Passive infinitive

The infinitive of a passive verb ends in -ī or -rī : capī 'to be captured, audīrī 'to be heard', etc.

in vincula dūcī iubet
sī vīs amārī, amā

The Perfect passive has an infinitive captus esse 'to have been captured', and there is also a rarely used Future passive infinitive made using the supine plus the passive infinitive īrī: captum īrī 'to be going to be captured'. It is typically used in indirect statements:

''occīsum īrī ab ipsō Milōne videō''

Deponent verbs

Most of the verbs ending in -or are true passives in meaning. However, there are a few which are ambivalent and can be either active or passive in meaning, such as vertor 'I turn' or 'I am turned', volvor 'I revolve' or 'I am rolled':

vertitur intereā caelum et ruit Ōceanō nox

In addition, there are a few verbs such as proficīscor 'I set out', polliceor 'I promise', cōnor 'I try' which despite their passive endings have an active meaning. These verbs are called deponent verbs:

ipse in Italiam profectus est

Although most deponent verbs are intransitive, some of them such as sequor 'I follow' can take a direct object:

hunc sequī sē iubet

Deponent verbs are frequently used in their perfect participle form :

''mediā nocte profectus ad hostium castra māne pervēnit''

The subjunctive mood

As well as the indicative mood illustrated above, which is used for stating and asking facts, and an imperative mood, used for direct commands, Latin has a subjunctive mood, used to express nuances of meaning such as "would", "could", "should", "may" etc.

Formation of the subjunctive

There are four tenses of the subjunctive, which in the verb faciō are as follows:

Present : faciam : 'I may do', 'I would do', 'I should do'
Imperfect : facerem : 'I would be doing', 'I should do'
Perfect : fēcerim : 'I have done', 'I did'
Pluperfect : fēcissem : 'I would or should have done'

The present subjunctive of 1st conjugation verbs ends in -em instead of -am: amem 'I may love, I would love'.
The present subjunctive of the verbs sum 'I am', possum 'I am able', volō 'I want', nōlō 'I don't want' and mālō 'I prefer', ends in -im: sim 'I may be, I would be', possim 'I may be able', velim 'I would like, I may wish', etc.
The imperfect subjunctive of every verb has the same form as the infinitive + -m: essem, possem, vellem, amārem, vidērem, īrem etc.

Uses of the subjunctive

The subjunctive has numerous uses, ranging from what potentially might be true to what the speaker wishes or commands should happen. It is often translated with "should", "could", "would", "may" and so on, but in certain contexts, for example indirect questions or after the conjunction cum 'when' or 'since', it is translated as if it were an ordinary indicative verb.
Often in English the subjunctive can be translated by an infinitive; for example, imperāvit ut īret becomes in more idiomatic English 'he ordered him to go'.

Potential subjunctive

The "potential" subjunctive is used when the speaker imagines what potentially may, might, would, or could happen in the present or future or might have happened in the past. The negative of this kind is nōn:

dūrum hoc fortasse videātur
quid si hoc fēcissem?
''nōn facile dīxerim quicquam mē vīdisse pulchrius''

Optative subjunctive

Another use is for what the speaker wishes may happen, or wishes had happened. The negative of this kind is nē:

utinam iam adesset!
''utinam ille omnīs sēcum suās cōpiās ēduxisset!''

Jussive subjunctive

It can also represent what the speaker commands or suggests should happen. The negative is again nē:

vīvāmus, mea Lesbia, atque amēmus
''nē... mortem timuerītis''

In indirect statements and questions

One important use of the subjunctive mood in Latin is to indicate that the words are quoted; this applies for example to subordinate clauses in indirect speech:

locum ubi esset facile inventūrōs

It also applies to all indirect questions:

quārē id faciam, fortasse requīris

When used in indirect speech or in an indirect question, the subjunctive is translated as if were the corresponding tense of the indicative.

Subjunctive after conjunctions

The subjunctive mood is very frequently used in subordinate clauses following conjunctions.

After ''''

Used with the indicative, the conjunction cum means 'at that time when', or 'whenever':

cum tacent, clāmant

Used with the subjunctive, however, it frequently means 'at a time when'. When cum is used with the Imperfect subjunctive, a common way of translating it is 'while':

cum sedērem domī trīstis, accurrit Venerius

With the Pluperfect subjunctive, it often means 'after X happened':

cum excessisset Aegyptō Antiochus, lēgātī... Cyprum nāvigant

It can also mean 'in view of the fact that' or 'since':

quae cum ita sint

Another, less common, meaning is 'though':

''nihil mē adiūvit, cum posset''

After ''''

When followed by the indicative, the conjunction ut can mean 'as' or 'as soon as' or 'when'. But with the subjunctive ut has the meaning 'that' or 'so that'.
It can represent purpose :

Crētam vēnit ut ibī quō sē cōnferret cōnsīderāret

It can also be used to introduce an indirect command :

imperāvit eī ut omnēs forēs aedificiī circumīret

It can also represent result :

idque sīc aedificāverat ut in omnibus partibus aedificiī exitūs habēret

Occasionally ut with the subjunctive can mean 'although'.

After ''''

After sī 'if', the subjunctive expresses an imagined or unreal situation:

quod, sī interfectus essem, accidere nōn potuisset
''sī revīvīscant et tēcum loquantur, quid respondēres?''

After ''''

After nē 'that not', the subjunctive can express a negative purpose:

hīnc nē exīre posset, ephorī valvās obstrūxērunt

It can also introduce a negative indirect command:

Tīmoleōn ōrāvit omnēs nē id facerent

The conjunction nē can also express a fear; in this case, the word 'not' must be omitted from the English translation:

verēns nē dēderētur

After ''''

When used with the indicative, dum means 'while' or 'as long as'. But when followed by the subjunctive, it often means 'until':

Verginius dum collēgam consuleret morātus

Another meaning is 'provided that':

''ōderint dum metuant''

After ''''

The conjunctions priusquam and antequam both mean 'before '. If the event actually happened, the verb is usually in the indicative mood; but when the meaning is 'before there was a chance for it to happen', the verb is subjunctive:

'' celeriter, priusquam ab adversāriīs sentiātur, commūnit''

After ''''

The conjunction quīn is always used after a negative verb or the equivalent, typically 'there is no doubt that', 'who does not know that...?', and so on. The words following quīn are always positive and usually state what was actually the case:

nōn dubitō quīn ad tē omnēs tuī scrīpserint
quis ignōrat quīn tria Graecōrum genera sint?

Another usage is after a negative verb such as 'I can't help doing' or 'he did not refrain from doing':

facere nōn possum quīn... tibī grātiās agam
Antiochus nōn sē tenuit quīn contrā suum doctōrem librum ēderet

Equally it can be used in sentences of the kind 'A didn't happen without B also happening':

nūllum adhūc intermīsī diem quīn aliquid ad tē litterārum darem

In sentences like the following, there is potential for confusion, since the quīn clause, though positive in Latin, is translated in English with a negative:

nēmo fuit militum quīn vulnerārētur
fierī nūllō modō poterat quīn Cleomenī parcerētur

In the following context, the words after quīn express not what actually happened but what very nearly happened:

''neque multum āfuit quīn castrīs expellerentur''

Subjunctive after '''' 'who'

Generic

The pronoun quī 'who' or 'which', when followed by a subjunctive, can mean 'a person such as' :

''quī modestē pārat, vidētur quī aliquandō imperet dignus esse''

Purpose

It can also mean 'in order to' :

''lēgātōs Rōmam quī auxilium peterent mīsēre''

Explanatory

Another meaning is 'in view of the fact that', as in the following example, said jokingly of a consul who was elected on the last day of the year:

''fuit mīrificā vigilantiā, quī suō tōtō cōnsulātū somnum nōn vīderit''

Reported speech

Another reason for using the subjunctive after quī is to show that the words of the quī clause are quoted or part of indirect speech:

Paetus omnīs librōs quōs frāter suus relīquisset mihī dōnāvit

Clearly here Paetus had written or stated "I am giving you all the books which my brother left me", and Cicero is quoting his words indirectly to Atticus.

The imperative mood

Present imperative

The imperative mood is used for giving direct orders. The active form can be made plural by adding -te:

dā mī bāsia mīlle, deinde centum!
''date dexterās fidemque!''

Deponent imperative

Deponent verbs such as proficīscor 'I set out' or sequor 'I follow' have an imperative ending in -re or -minī :

patent portae: proficīscere!
''sequiminī mē hūc intrō ambae''

Passive imperative

The passive imperative is almost never found. It has the same endings as the deponent imperative:

''neu bellī terrēre minīs''

Negative commands

An imperative is usually made negative by using nōlī plus the infinitive. However, in poetry an imperative can sometimes be made negative with the particle nē:

nōlīte mīrārī
nē mē terrēte timentem, obscēnae volucrēs!

A negative order can also use the perfect subjunctive:

''dē mē nihil timuerīs''

Future imperative

Latin also has a future imperative or 2nd imperative, ending in -tō, which is used to request someone to do something at a future time, or if something else happens first:

sī quid acciderit,... scrībitō

This imperative is very common in early writers such as Plautus and Cato, but it is also found in later writers such as Martial:

ubi nōs lāverimus, sī volēs, lavātō
crūdam si edēs, in acētum intinguitō
rīdētō multum quī tē, Sextille, cinaedum dīxerit et digitum porrigitō medium.

Some verbs have only the second imperative, for example scītō 'know', mementō 'remember'.

nunc scītōte mē esse in summā sollicitūdine
sed hoc mementōte

3rd person imperative

A 3rd person imperative also ending in -tō, plural -ntō exists in Latin. It is used in very formal contexts such as laws:

''iūsta imperia suntō, īsque cīvēs... pārentō''

Other ways of expressing a command

Other requests are made with expressions such as cūrā ut 'take care to...', fac ut 'see to it that...' or cavē nē 'be careful that you don't...'

cūrā ut valeās

The future indicative can be used for polite commands:

''Pīliae salūtem dīcēs et Atticae''

The infinitive

Although often referred to as a 'mood', the Latin infinitive is usually considered to be a verbal noun rather than a mood.
Latin has three infinitives in the active voice, and three passive. Since faciō is irregular in the passive, they are here shown using the verb capiō 'I capture':
Active:

Present : capere : 'to capture, to be capturing'
Perfect : cēpisse : 'to have captured'
Future : captūrus esse : 'to be going to capture'

Passive:

Present : capī : 'to be captured'
Perfect : captus esse : 'to have been captured'
Future : captum īrī : 'to be going to be captured'

The infinitives of sum 'I am' are esse, fuisse, and futūrus esse. Possum 'I am able' has infinitives posse and potuisse, and volō 'I want' has velle and voluisse. Neither of these verbs has a Future infinitive, and the Present infinitive is used instead.
The Future infinitive is used only for indirect statements.
The passive Future infinitive is rare, and is frequently replaced with a phrase using fore ut.
Rarer tenses of the infinitive, for example captus fore or captūrus fuisse, are sometimes found in indirect speech.

Uses of the infinitive

The infinitive can be used as the subject, complement, or the object of a verb:

vīvere est cōgitāre
''errāre, nescīre, dēcipī... turpe dūcimus''

Prolative infinitive

It can also be used, as in English, dependent on an adjective, or with verbs such as possum 'I am able' or volō 'I want':

dulce et decōrum est prō patriā morī
nōn possum haec ferre

It is likewise used, as in English, with verbs such as iubeō 'I order', vetō 'I forbid', patior 'I allow', volō 'I want' and so on, where the subject of the complement clause is in the accusative case:

volō tē hoc scīre

However, other verbs of similar meaning, such as imperō 'I order', persuādeō 'I persuade', and hortor 'I urge', are not used with an infinitive, but with ut and the subjunctive mood:

''hortātur mē ut senātūi scrībam''

Historic infinitive

An infinitive is sometimes used to represent a series of repeated actions:

clāmāre omnēs
equitātus interim eōrum circum mūnītiōnēs Caesaris vagārī

Accusative and infinitive (indirect statement)

A very common use of the infinitive in Latin, in which it differs from English, is its use for indirect statements, that is for sentences where a subordinate clause is dependent on a main verb meaning 'he says', 'he knows', 'he pretends', 'he believes', 'he thinks', 'he finds out' and so on. In Latin, instead of 'they pretend that they want', the idiom is to say 'they pretend themselves to want':

sē pācem velle simulant

Similarly 'I'm glad you've arrived safely' becomes 'I am glad you to have arrived safe':

salvom tē advēnisse gaudeō

In this construction, the subject of the infinitive is in the accusative case.
So common is this construction in Latin, that often the verb 'he said' is simply omitted if it is clear from the context, the accusative and infinitive alone making it clear that the statement is reported:

rem atrōcem incidisse

The rule of tense in an accusative and infinitive construction is that the present infinitive is generally used for actions contemporary with the main verb, the perfect for actions which preceded it, and the future for actions which followed it. An example of the future infinitive using the future participle is the following:

Valerium hodiē audiēbam esse ventūrum

Often the esse part of a future active or perfect passive infinitive is omitted:

frātrem interfectum audīvit

Less common is the periphrastic perfect infinitive, used when a potential pluperfect subjunctive is converted into an indirect statement:

Clōdium negant eō diē Rōmam, nisī dē Cȳrō audīsset, fuisse reditūrum

The above example also illustrates another feature of indirect statement, that a negative indirect statement is usually represented by the use of the main verb negō 'I deny'.

Other ways of expressing 'that'

Not every subordinate clause which starts with the conjunction 'that' in English is translated with an accusative and infinitive. In some contexts ut with the subjunctive is required, for example after a verb of happening:

accidit cāsū ut lēgātī Prūsiae Rōmae... cēnārent

In other circumstances a clause with quod 'the fact that' is used with the indicative:

praetereō quod eam sibī domum dēlēgit

In less educated authors quod could even substitute for the accusative an infinitive, though this did not become common until the second century:

lēgātī renūntiāvērunt quod Pompeium in potestāte habērent

This type of clause with quod gradually took over from the Accusative and infinitive construction and became the usual way of expressing indirect speech in modern Romance languages which are descended from Latin.

Participles

Unlike Greek, Latin is deficient in participles, having only three, as follows:

Present : faciēns : 'doing/making' or 'while doing/making'
Perfect : factus : 'done' or 'having been made'
Future : factūrus : 'going to do/make'

The Romans themselves considered the gerundive also to be a participle, but most modern grammars treat it as a separate part of speech:

Gerundive : faciendus : 'needing to be made'

There is no active perfect participle in most verbs, but in deponent verbs, the perfect participle is active in meaning, e.g. profectus, 'having set out'.
The verb sum 'I am' has no present or perfect participle, but only the Future participle futūrus 'going to be'. However the derived verb absum 'I am absent' has a present participle absēns 'absent'.

Uses of participles

Adjectival participle

Participles have endings like those of adjectives, and occasionally they are used as though they were adjectives. If so, they refer to the state or condition that a thing or person is in:

aquā ferventī... perfunditur
occīsōs sepelīvit

Participle as a verb

More frequently, however, a participle is more like a verb, and if one action follows another, it can often replace the first of two verbs in a sentence:

Caesar Cascae bracchium arreptum graphiō trāiēcit

Literally, 'Caesar with writing instrument pierced for Casca the grabbed arm '
Participles can frequently be translated into English using a clause with 'when':

quaerentique viro 'satin salve?' 'minime!' inquit.
cōnātusque prōsilīre aliō vulnere tardātus est

'-ing' and 'who' are other possible translations:

currēns Lepta vēnit
strīctō gladiō, ad dormientem Lucrētiam vēnit

Apart from 'when' and 'who', other translations are possible, such as 'if', 'since', or 'although':

oculus sē nōn vidēns, alia cernit

A participle phrase can also stand for a noun clause, as in the following example:

captī oppidī signum ex mūrō tollunt

Normally a Present participle represents an action which is simultaneous with the main event, and a Perfect participle represents one which has already happened. In the following example, however, the Perfect participle represents the result following the main action:

crīnīs scindit... solūtōs

Participles are much commoner in Latin than in English. Sometimes multiple participles can be used in a single sentence:

noctū lūmine appositō experrēcta nūtrīx animadvertit puerum dormientem circumplicātum serpentis amplexū. quō aspectū exterrita clāmōrem sustulit.

Ablative absolute

The phrase strīctō gladiō above is an example of a common idiom in which a noun and participle are put in the ablative case to represent the circumstances of the main event. This absolute construction in Latin is called an "ablative absolute" and is comparable to the Greek genitive absolute or the English nominative absolute. Other examples are:

in hostēs signō datō impetum fēcērunt
at pater Aenēas, audītō nōmine Turnī, dēserit mūrōs

The present participle can also be used in an ablative absolute:

at illa audientibus nōbīs 'ego ipsa sum' inquit 'hīc hospita'
nec imperante nec sciente nec praesente dominō

The verb sum has no participle, except in the compound forms absēns 'absent' and praesēns 'present'. To make an ablative absolute with 'to be', the words are put in the ablative, and the verb is simply omitted:

puerulō mē
hīs cōnsulibus Fīdēnae obsessae, Crustumeria capta

The gerundive

The gerundive is a verbal adjective ending in -ndus. It is usually passive in meaning. The usual meaning of the gerundive is that it is necessary for something to be done. Often the word 'must' is a suitable translation:

nunc est bibendum
Catō inexpiābilī odiō dēlendam esse Carthāginem... prōnūntiābat

If a word is added to show by whom the action must be done, this word is put in the dative case.
Because it is passive in meaning, the gerundive is usually formed from transitive verbs. However, intransitive verbs such as eō 'I go' and persuādeō 'I persuade', which can be used passively in an impersonal construction, can also have an impersonal gerundive, ending in -um:

mihī Arpīnum eundum est
persuādendum iūdicī est

The gerundive after ad can also be used to express purpose :

L. Septimium tribūnum militum ad interficiendum Pompeium mīsērunt
''hunc Dātamēs vīnctum ad rēgem dūcendum trādit Mithridātī''

The gerund

The gerund is a verbal noun ending in -ndum, -ndī, or -ndō. Although identical in form to a neuter gerundive, and overlapping the gerundive in some of its uses, it is possible that it has a different origin.
Gerunds are usually formed from intransitive verbs, and are mainly used in sentences such as the following where the meaning is 'by doing something', 'of doing something', or 'for the purpose of doing something'. A gerund is never used as the subject or direct object of a verb.

veniendō hūc exercitum servāstis
aqua nitrōsa ūtilis est bibendō
idōneam ad nāvigandum tempestātem
sacrificandī causā, Delphōs ēscendī

Occasionally a gerund can be made from a transitive verb and can take a direct object:

subabsurda dīcendō rīsūs moventur

They can also be formed from deponent verbs such as ingredior 'I enter':

aliīs timor hostium audāciam flūmen ingrediendī dedit

However, if the verb is transitive, a phrase made of noun + gerundive is often substituted for the gerund:

lignum āridum māteria est idōnea ēliciendīs ignibus

The supine

The supine is a rarely used part of the verb ending in -tum or -sum. When a verb is given in a dictionary with its four principal parts, such as ferō, ferre, tulī, lātum 'I bring' or mittō, mittere, mīsī, missum 'I send', the supine is the fourth part.
The supine is identical in form with the accusative case of 4th declension verbal nouns such as adventus 'arrival', mōtus 'movement', reditus 'return', etc., but it differs from them in that it is a verb as well as a noun, and can sometimes take a direct object.

Supine in -um

The supine is normally used to express purpose, when combined with a verb of movement such as eō 'I go' or mittō 'I send':

lūsum it Maecenās, dormītum ego Vergiliusque
spectātum veniunt, veniunt spectentur ut ipsae

In the following example it takes a direct object:

lēgātōs ad Caesarem mittunt rogātum auxilium

The accusative of the supine is also used to make the rare future passive infinitive, for example, captum īrī 'to be going to be captured', which can be used in indirect statements referring to the future :

ante reditum eius negōtium cōnfectum īrī putō

Supine in -ū

There is another form of the supine, an Ablative in -ū, found with certain verbs only. But this cannot take an object. It is used in phrases such as mīrābile dictū 'amazing to say', facile factū 'easy to do':

dictū quam rē facilius est