The infinitive is the “to-” form of the verb: to hold, to walk, to be. The infinitive has no mood, and it is not conjugated for person and number. So the only variations for the infinitive are the voice (active or passive) and the tense. The infinitive also only uses three tenses, present, perfect, and future, and has no future passive, so that trims it down to five total forms. For example, here are all five infinitive forms of amo.

Now we'll take each form individually and show examples from each conjugation. Except for the present passive of the third conjugation, all conjugations are handled the same way.

We've already been learning the present active infinitive of verbs, since it is the second principal part:

• amāre, to love
• habēre, to hold
• regere, to rule
• audire, to hear

We form the present passive infinitive by changing the final -e of the present active infinitive to -ī, except for the third conjugation, where we replace the whole -ere ending with -ī.

• amāre, to love → amārī, to be loved
• habēre, to hold → habērī, to be held
• regere, to rule → regī, to be ruled
• audīre, to hear → audīrī, to be heard

We form the perfect active infinitive by adding -isse to the perfect stem, found by dropping the -ī from the third principal part.

• amāvī, I loved → amāvisse, to have loved
• habuī, I held → habuisse, to have held
• rexī, I ruled → rexisse, to have ruled
• audīvī, I heard → audīvisse, to have heard

We form the perfect passive infinitive much like we form the perfect passive indicative that we learned in the last chapter, but instead of combining the fourth principal part with sum, es, est, sumus, estis, sunt, we combine it with esse, the infinitive of sum.

• amātus sum, I have been loved → amātus esse, to have been loved
• habitus sum, I have been held → habitus esse, to have been held
• rectus sum, I have been ruled → rectus esse, to have been ruled
• audītus sum, I have been heard → audītus esse, to have been heard

Note that the -us/-a/-um ending is declined to match the subject in gender, case, and number, just like we learned last lesson for the perfect passive.

We form the future active infinitive by repacing the -us, -a, -um ending of the fourth principal part with -ūrus, -ūra, -ūrum to form the future participle, and then adding esse.

• amātūrus esse, to be about to love
• habitūrus esse, to be about to hold
• rectūrus esse, to be about to rule
• audītūrus esse, to be about to hear

There's no very comfortable translation for the future active infinitive in English, so we express it by something like “to be about to [something]”. The basic meaning is to be doing something in the future.

Again, the -us/-a/-um ending is declined to match the subject in gender, case, and number.

The infinitive has several different uses, many of which match uses of the infinitive in English, so they will come naturally. Some are expressed in other ways in English, though, so we'll see how to handle each type of case.

An infinitive can be used in place of a noun as the subject or object of a verb. Infinitives used as nouns are always neuter singular, and either nominative or accusative depending on their place in the sentence.

When an infinitive is used as a noun, it can usually be translated literally in English, but in many cases it is easier to use a gerund. For example:

• Ambulare est bonum. - To walk is good. Walking is good.
• Semper cupivi navigare. - I always wanted to sail.
• Duces amant laudari. - Leaders love to be praised. Leaders love being praised.
• Lucius temptabat videre equos. - Lucius was trying to see the horses.

Some verbs require an infinitive to complete their meaning, just as they often do in English. For example, dēbeō when it means ought and cōnstituō when it means decide.

• Ad Italiam ambulare constituimus. - We decided to walk to Italy.
• Urbs bona a duce bono regi debet. - A good city ought to be ruled by a good leader.

Some verbs may be followed by an accusative representing the direct object of the verb as usual, and an infinitive representing the action of that object. In that case, the subject of the infinitive is the word in the accusative. It's simpler than it sounds. Some verbs that allow this construction are cogō (force, compel), jubeō (order), and prohibeō (prevent from).

• Marcus agricolas venire in oppidum coegit. - Marcus forced the farmers to come into town.
• Nautas cras non navigare jubebo. - I will order the sailors not to sail tomorrow.
• Eos urbem relinquere prohibebimus. - We will prevent them from leaving the city.

Note in the last example that if we translated the infinitive literally, it wouldn't sound right in English:

• We will prevent them to leave the city.

That's one example where in English we prefer to use the gerund “leaving,” because we use the preposition “from” to help express the meaning of prohibeo.

An indirect statement is a sentence like, “He says that his horse is great.” In English, the word that usually introduces the indirect statement. In Latin, the verb of the indirect statement is placed in the infinitive, while the subject of the indirect statement is in the accusative. In practice, they look a lot like the Infinitive with Accusative Subject that we just learned that follows verbs of forcing. Indirect statements follow verbs of saying, knowing, hearing, etc.

• Dicit primum equum esse magnum. - He says that the first horse is great. (He says the first horse to be great.)

Note that we could translate the infinitive as “to be,” as I did in parentheses, and it would technically make sense, but it sounds stilted in English. It sounds much better to turn it into an indirect statement preceded by “that,” although “that” can be left out in simple sentences: “He says the first horse is great.”

• Eis monui villam deletam esse. - I warned them that the farmhouse had been destroyed. (I warned to them the farmhouse to have been destroyed.)
• Julius audivit regem pecuniam omnibus daturum esse. - Julius heard that the king will give everyone money. (Julius heard the king about to give everyone money.)

The tense of an infinitive shows the time of the infinitive verb relative to the main verb of the sentence. If the infinitive action happened before the main verb, we use the perfect tense of the infinitive. If the two verbs happen at the same time, we use the present tense for the infinitive. If the infinitive will happen in the future compared to the main verb, we use the future tense of the infinitive.

So in the last two examples above, deletam esse is the perfect passive infinitive because the destruction of the farmhouse happened before the warning about it. Likewise, daturum esse is the future active infinitive because the giving will happen after Julius has heard about it. It doesn't matter what tense the main verb is in; it only matters whether the infinitive takes place before, after, or at the same time as the main verb.

Note that there is no future passive infinitive, so we can't use the infinitive to say something like:

• Julius heard that money will be given to everyone by the king. (Julius heard money about to be given to the king.)

Because “will be given” would need to be translated by the future passive infinitive, which doesn't exist. So we have to turn it around into the active:

• Julius heard that the king will give money to everyone.

• ecclesia, -ae, f., church
• gloria, -ae, f., glory
• gratia, -ae, f., grace, (pl.) thanks
• hostia, -ae, f., host, victim
• patriarcha, -ae, m., patriarch
• propheta, -ae, m., prophet

• purus, -a, -um, pure

• adjuvō, -adjuvāre, -adjuvāvī, -adjuvātum, help
• adorō, -āre, -āvī, -ātum, adore
• celebrō, -āre, -āvī, ātum, celebrate
• donō, -āre, -āvī, -ātum, give, donate
• elevō, -āre, -āvī, -ātum, elevate
• glorificō, -āre, -āvī, -ātum, glorify, praise
• judico, -āre, -āvī, -ātum, judge
• mundō, -āre, -āvī, -ātum, clean, purify
• rogō, -āre, -āvī, -ātum, ask, ask for
• sperō, -āre, -āvī, -ātum, hope, hope for

• jubeō, jubēre, jussī, jussum, order, command

Julia et Maria erant sorores quae in villa parva ad Romam habitaverunt. Olim pater earum litteras eis misit. Eas jussit venire ad portum quarto die anni et exspectare navem eius. Constituerunt ambulare in via brevi per silvam. Puellae amabant ambulare. Multos aves et animalia viderunt. Ad animalia magna clamaverunt et speraverunt timeri ab eis. Quinque horas ambulaverunt et ad portum meridie pervenerunt. Cupiverunt navem patris advenisse, sed eam non viderunt. Tandem (finally) in portum venit et celebraverunt.

1. I hope the dog came to town with my father.
2. Running is a good sport.
3. Maria, you ought to be helped by your brothers.
4. I said to them that the ship was about to arrive.
5. We asked the king to give food to the poor.
6. Agatha has a cat that used to like to fight with dogs.
7. Marcus, oughtn't your hands be cleaned before dinner?
8. The soldiers prevented the enemy from seizing the city.
9. Being ruled by a general is often bad.
10. Julius, order the men to stand in the middle of the town at noon.

Give an English word related to each Latin word in the vocabulary.

This pretty well takes care of the infinitives. We'll see a few more minor ways to use them, but we've learned all the forms, so it will be easy to use them in other situations. In the next lesson, we'll cover a couple common irregular verbs, and then we'll be ready to move on to the subjunctive mood, which barely exists in English but is very common in Latin.

Julia et Maria erant sorores quae in villa parva ad Romam habitaverunt. Olim pater earum litteras eis misit. Eas jussit venire ad portum quarto die anni et exspectare navem eius. Constituerunt ambulare in via brevi per silvam. Puellae amabant ambulare. Multos aves et animalia viderunt. Ad animalia magna clamaverunt et speraverunt timeri ab eis. Quinque horas ambulaverunt et ad portum meridie pervenerunt. Cupiverunt navem patris advenisse, sed eam non viderunt. Tandem (finally) in portum venit et celebraverunt.

Julia and Maria were sisters who lived in a small farmhouse near Rome. Once upon a time, their father sent them a letter. He ordered them to come to the harbor on the fourth day of the year and watch for his ship. They decided to walk on the short road through the forest. The girls loved to walk. They saw many birds and animals. They shouted at the large animals and hoped to be feared by them. They walked for five hours and arrived at the harbor at noon. They wanted their father's ship to have arrived, but they did not see it. Finally it came into the harbor, and they celebrated.

1. I hope the dog came to town with my father. - Spero canem venisse ad oppidum cum patre meo.
2. Running is a good sport. - Currere est ludus bonus.
3. Maria, you ought to be helped by your brothers. - Debes, Maria, adjuvari a fratribus tuis.
4. I said to them that the ship was about to arrive. - Eis dixi navem perventuram esse.
5. We asked the king to give food to the poor. - Regem rogavimus cibum miseris dare.
6. Agatha has a cat that used to like to fight with dogs. - Agatha felem quae amabat cum canibus pugnare habet.
7. Marcus, oughtn't your hands be cleaned before dinner? - Nonne, Marce, manus tuae debent mundari ante cenam?
8. The soldiers prevented the enemy from seizing the city. - Milites prohibuerunt hostes occupare urbem.
9. Being ruled by a general is often bad. - Regi ab imperatore malum saepe est.
10. Julius, order the men to stand in the middle of the town at noon. - Jube, Juli, viros in medio oppido meridie stare.

Give an English word related to each Latin word in the vocabulary.

• ecclesia, -ae, f., church, ecclesiastical
• gloria, -ae, f., glory, glory, glorious
• gratia, -ae, f., grace, (pl.) thanks, gratitude
• hostia, -ae, f., host, victim, host
• patriarcha, -ae, m., patriarch, patriarch
• propheta, -ae, m., prophet, prophet, prophecy

• purus, -a, -um, pure, pure, purify

• adjuvō, -adjuvāre, -adjuvāvī, -adjuvātum, help, adjust, adjudicate
• adorō, -āre, -āvī, -ātum, adore, adore, adoration
• celebrō, -āre, -āvī, ātum, celebrate, celebrate
• donō, -āre, -āvī, -ātum, give, donate, donate
• elevō, -āre, -āvī, -ātum, elevate, elevate
• glorificō, -āre, -āvī, -ātum, glorify, praise, glorify
• judico, -āre, -āvī, -ātum, judge, judge, judicial
• mundō, -āre, -āvī, -ātum, clean, purify, ??
• rogō, -āre, -āvī, -ātum, ask, ask for, interrogate
• sperō, -āre, -āvī, -ātum, hope, hope for, ??

• jubeō, jubēre, jussī, jussum, order, command, jussive