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Future perfect

The future perfect tense is used for an action that will have been completed in the future by the time something else has happened.

English example: "I will have seen the movie by the time it comes out."

To form the future perfect, take the perfect stem and add the future perfect endings:

Note the similarities to the future tense of sum, except for the third person plural ending -erint^[1] in place of -erunt, which serves as the perfect ending instead.

Hence: amāverō, I will have loved; vīderitis, you (pl.) will have seen

1. ↑ -int as an ending is rare; -erint and sint are two of the most common

Pluperfect

The pluperfect tense is used to describe something in the past that happened before another event in the past.

English example: "I had graduated by the time I applied for a job."

To form the pluperfect, take the perfect stem and add the pluperfect endings:

Hence: amāveram, I had loved; vīderātis, you (pl.) had seen

Examples

De Acutiliano autem negotio quod mihi mandaras (mandaveras), ut primum a tuo digressu Romam veni, confeceram. (Cicero, Ad Atticum 1.5)

"But as to the business of Acutilius that you had entrusted with me, I had already taken care of it when I came to Rome first thing after your departure." Note the relationship of the pluperfect verbs mandaras (-aras is a common contraction for -averas) and confeceram to the perfect verb veni.

Ego certe meum officium praestitero. (Caesar, De Bello Gallico IV)

"I certainly will have prevailed in my duty."