Latin Verbs - Infinitives

When you look up a Latin verb in a Latin-English lexicon or dictionary, you will see four entries for most verbs. The first entry is the present, active, singular, first person form of the verb. The next entry, usually abbreviated to "-are," "-ere" or "-ire," is the infinitive. More specifically, it's the present active infinitive, which is translated into English as "to" plus whatever the verb means.

Example: Laudo, -are, -avi, -atus. Praise

Laudo is a first conjugation verb and therefore has an infinitive ending in "-are." The entire present active infinitive of laudo is laudare, which we translate into English as "to praise." (Laudo literally means "I praise.")
Laudari is the present passive infinitive of laudo and means "to be praised."

Most verbs have six infinitives:

1. Present Active
2. Present Passive
3. Perfect Active
4. Perfect Passive
5. Future Active
6. Future Passive (rare)

The perfect active infinitive is formed from the perfect stem. In our example of a first conjugation verb, laudo, the perfect stem is found on the third principal part, laudavi, which is listed in the dictionary simply as "-avi." Remove the personal ending ("i") and add "isse" -- laudavisse -- to make the perfect active infinitive. The perfect passive infinitive is formed from the fourth principal part, in our example, laudatus, plus "esse." The perfect passive infinitive is laudatus esse. The fourth principal part also informs the future infinitives. The future active infinitive is laudaturus esse and future passive infinitive is laudatum iri.

First Conjugation

1. (Present Active) amare (love)
2. (Pres. Passive) amari
3. (Perf. Act.) amavisse
4. (Perf. Pass.) amatus esse
5. (Fut. Act.) amaturus esse
6. (Fut. Pass.) amatum iri

Second Conjugation

1. monere (warn)
2. moneri
3. monuisse
4. monitus esse
5. moniturus esse
6. monitum iri

Third Conjugation

1. regere (rule)
2. regi
3. rexisse
4. rectus esse
5. recturus esse
6. rectum iri

Fourth Conjugation

1. audire (hear)
2. audiri
3. audivisse
4. auditus esse
5. auditurus esse
6. auditum iri

On Interpreting the Infinitive

Although it may be easy enough to translate the infinitive as "to" plus whatever the verb is (plus whatever person and tense markers may be required), it can be hard to explain the infinitive. It acts like a verbal noun, for which reason, it it sometimes taught alongside the gerund.

Latin Composition's Bernard M. Allen says that only 3/8 of the times that an infinitive is used in Latin, it is an indirect statement. An example of an indirect statement is: "She says that she is tall." In Latin, the "that" wouldn't be there. Instead the construction would involve a regular statement she says (dicit) followed by the indirect part, with the subject "she" in the accusative case followed by the present infinitive (esse):

Dicit eam esse altam.
She says (that) she [acc.] is [infinitive] tall [acc.].

Allen says that Bennett's Grammar provides a rule for the tense of the infinitive that is only applicable to the present infinitive in indirect statement. Bennett's rule is "'The Present Infinitive represents an act as contemporaneous with that of the verb on which it depends.'" Bernard prefers the following: "'In Indirect Statements the present infinitive represents an act as contemporaneous with the time of verb on which it depends. In other substantive uses it is merely a verbal noun, without any tense force.'" As an example of why tense is a difficult concept with present infinitives, Allen says that in Cicero and Caesar, 1/3 of their present infinitives follow the verb possum 'to be able'. If you are able to do something, that ability precedes the time of the statement.

"The Latin Present Infinitive," by Bernard M. Allen. The Classical Journal, Vol. 19, No. 4 (Jan., 1924), pp. 222-225

Index of Quick Tips on Latin Verbs

• Types of Latin Verbs
• Latin Supine
• Latin Verb Endings
• Latin Infinitives
• Latin Verbs - Internal Thematic Vowel
• Latin Verbs - Person and Number
• Latin Verbs - Prepositions in Verbs
• Latin Verbs - Sequence of Tenses in Indirect Discourse
• Latin Words - Where Do You Add on Endings?
• Passive Periphrastic

com/od/latinlearning/qt/passiveperiphra.htm]Passive Periphrastic