Future Active Periphrastic

The future active periphrastic combines the future active participle in -ūrus, -a, -um with a form of sum: scrīptūrus sum “I am going to write,” scrīptūra erat “she was about to write.” It presents an action as prospective from a reference point and often adds intention, preparation, imminence, or destiny. The ordinary synthetic future scrībam simply places the writing in the future; the periphrastic invites the listener to view the subject as poised or committed to perform it.

The construction is productive in Classical Latin and belongs to (neutral and formal Classical prose) as well as (literary) narrative. Its nearest English equivalent varies among “be going to,” “be about to,” “intend to,” and plain “will.” Teaching examples below use macrons; attributed text would retain its source spelling. Its relation to the synthetic future is developed in Future and Future Perfect Pragmatics.

Formation from the fourth principal part

Start from the supine, traditionally the fourth principal part. Remove -um and add -ūrus, -ūra, -ūrum. The resulting participle declines like a first-and-second-declension adjective.

Irregular principal parts remain visible: agō, ēgī, āctum gives āctūrus; veniō, vēnī, ventum gives ventūrus; sum, fuī, futūrus supplies futūrus directly. Deponents also have active future participles: proficīscor, profectus sum gives profectūrus “about to set out.” There is no shortcut from an English translation; consult the supine or dictionary form.

Scrīptūrus agrees with masculine singular Mārcus, monitūra with feminine singular Tullia, and profectūrī with masculine plural legātī. The object keeps the case required by the participle's verb: accusative epistulam and amīcam. The construction is active, not passive.

What the form of sum contributes

The participle remains prospective; sum locates the vantage point and supplies mood, person, and number.

The imperfect erant places the intention in the past and, by itself, leaves open whether the departure happened; the following clause says it did not happen then. Present es makes factūrus a current plan about a later act. The periphrastic itself does not guarantee fulfillment.

The periphrastic can be inflected throughout the indicative and subjunctive, including perfect-system forms such as factūrus fuī and factūrus fueram. These forms do more than mechanically move a plan backward: with past indicative forms of sum, Classical Latin often uses the construction where English has an unfulfilled “would have done” or “was prepared to do.” In indirect counterfactual apodoses, factūrum fuisse is especially important. Learners should therefore master the more frequent forms with sum, eram, sim, essem, and infinitive esse first, then interpret perfect-system combinations from their conditional and discourse context.

Plain future versus prospective periphrastic

The synthetic future is semantically broad. It can predict, promise, command politely, or simply place an event later. The periphrastic foregrounds the subject's orientation toward that action.

The first is a neutral future. The second points to preparation and a settled plan. Yet the distinction is pragmatic, not absolute: context can make a periphrastic sound like a plain prediction, especially with futūrus “going to be / destined to be.” Conversely, a synthetic future can express firm intention.

Here futūrus est is the future active periphrastic of sum. English naturally says “will become” or “is destined to be,” because literal “is going to be” may miss the predictive force.

Intention, imminence, and destiny

An animate subject often encourages intention: quid factūrus es? asks for a plan. Immediate circumstances encourage imminence: a speaker at the door may be exitūrus. With inanimate subjects or long-range forecasts, intention is impossible, so prediction or destiny remains.

The storm has no intention; visible evidence supports prediction. In the last example, imperfect subjunctive esset belongs to an embedded question in secondary sequence, while valitūrum is neuter singular because it agrees with illud cōnsilium. English “would prove” expresses future-in-the-past more naturally than “was going to be strong.”

Future infinitive in indirect statement

The construction supplies Latin's future active infinitive: an accusative future participle plus esse. It agrees with the accusative subject of indirect statement.

Ventūrum is masculine singular when sē refers to a man; reditūram is feminine because sē refers to Tullia; petītūrōs agrees with masculine plural legātōs. English “will/would” does not display that agreement, which is why translating before parsing causes errors.

In compressed usage esse may be omitted, especially in (literary) or tightly constructed indirect discourse, but the participle still carries accusative agreement. With verbs that lack a usable future active participle, or where a future passive idea is needed, Latin can use fore ut plus a subjunctive; that is a neighboring construction, not a reason to invent a participle.

Participial use without sum

The future active participle can modify a noun without forming the periphrastic. It can express purpose or intention, particularly with verbs of motion:

Here petītūrī agrees with legātī, but vēnērunt is the only finite verb. Supplying sunt would change the syntax. Outside the especially frequent futūrus and ventūrus, this independent participial use is more characteristic of poetry, Livian historical style, and later Latin than of ordinary Ciceronian prose (literary/formal). It helps explain the periphrastic's prospective meaning, but it is not itself a compound tense.

Common Mistakes

1. Forming the participle from the present stem

2. Failing to make the participle agree with the doer

3. Translating the form as future progressive

4. Keeping nominative agreement in indirect statement

5. Confusing prospective action with obligation

Key Takeaways

Build the future active participle from the supine stem plus -ūrus, -a, -um, make it agree with the prospective doer, and use sum to locate that prospect in tense and mood. The construction often highlights plan, imminence, or destiny, unlike the broader synthetic future. In indirect statement it becomes accusative plus esse, and without sum it remains a participle rather than a compound tense.