Future Perfect | Department of Classics
classics.osu.edu › Tense › PerfectTo form the future perfect active indicative, find the perfect stem (3rd principle part less the final "i"), and add the personal endings. Note: the personal endings are almost the same as the future of sum. (The 3rd plural future of sum is erunt; but the 3rd plural personal ending for the future perfect is, as below, -erint.)