Accusativus cum infinitivo

In grammar, accusative and infinitive is the name for a syntactic construction of Latin and Greek, also found in various forms in other languages such as English and Spanish. In this construction, the subject of a subordinate clause is put in the accusative case (objective case in English) and the verb appears in the infinitive form. Among other uses, information may be given in this form to indicate indirect speech, also called indirect discourse.

The construction is often referred to by the Latin term Accusativus cum infinitivo, frequently abbreviated ACI.

The accusative and infinitive is the usual grammatical construction by means of which Classical Latin expressed indirect statements, that is, statements which report what someone has said, thought, felt, etc. Whereas a direct statement would say

the indirect statement might say

Latin tends not to use the word "that" to introduce indirect statements. Rather, an accusative subject is used with an infinitive to develop the appropriate meaning. For example, translating the aforementioned example into Latin:

Sē here is an accusative reflexive pronoun referring back to the subject of the main verb i.e. Iūlia ; esse is the infinitive "to be."

Note that the tense of the infinitive, translated into English, is relative to the tense of the main verb. Present infinitives, also called contemporaneous infinitives, occur at the time of the main verb. Perfect infinitives (prior infinitives) occur at a time before the main verb. Future infinitives (subsequent infinitives) occur at a time after the main verb. For example, the contemporaneous infinitive in this sentence,

would still be translated "They said he was helping her," even though iuvāre is classified in Latin as a present active infinitive of the first conjugation.

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