[THE TENSES OF THE INDICATIVE.]
[1732.] I. The tense of a subordinate indicative often indicates a close relation of time with the tense of the leading verb, particularly in cases of repeated contemporaneous or antecedent action. The subordinate sentence in such combinations is said to have Relative time.
[1733.] (1.) The subordinate indicative tense may express action concurrent with the main action. Two concurrent sentences are usually put in the same tense.
Concurrent action is said to be (a.) congruent, when two actions merely cover the same time: as, dum legō, adsentior, TD. 1, 24, as long as I am reading, I assent. dum necesse erat, ūnus omnia poterat, RA. 139, so long as it had to be, one man controlled the world. dum Latīnae loquentur litterae, quercus huic locō nōn deerit, Leg. 1, 2, as long as Latin literature has the gift of speech, this spot will not lack its oak. vīxit, dum vīxit, bene, T. Hec. 461, he lived well all the time he lived. quoad potuit, fortissimē restitit, 4, 12, 5, as long as he could, he made a manful stand. Or (b.) coincident, when one action is virtually the same as the other: as, cum tacent, clāmant, C. 1, 21, while they are dumb, they cry out, i.e. their silence is as telling as a shout. fēcistī mihī̆ pergrātum, quod Serāpiōnis librum mīsistī, Att. 2, 4, 1, you have obliged me very much by sending Serapio’s book.
[1734.] (2.) The subordinate indicative tense may express action contemporaneous, antecedent, or subsequent, in relation to the main action.
[1735.] (a.) Action contemporaneous with a main present is expressed by a present, with a main future or virtual future, by a future, with a main secondary tense by an imperfect: as,
quod est, eō decet ūtī, CM. 27, what you have, that you should avail yourself of. hōrologium mittam, sī erit sūdum, Fam. 16, 18, 3, I will send the clock, if it is pleasant ([1625]). paulātim dabis, sī sapiēs, T. Hau. 870, you’ll give in driblets, if you are wise. cum relaxāre animōs volent, caveant intemperantiam, Off. 1, 122, when they want to unbend, let them beware of excess ([1625]; [1718]). omnia deerant, quae ad reficiendās nāvēs erant ūsuī, 4, 29, 4, they were out of everything that was serviceable for repairing their vessels.
[1736.] (b.) Action antecedent to a main present is expressed by a perfect, to a main future or virtual future by a future perfect, to a main secondary tense by a pluperfect: as,
quōcumque aspexistī tuae tibī̆ occurrunt iniūriae, Par. 18, wherever you turn your gaze, you are confronted by your own abominable acts. cum posuī librum, adsēnsiō omnis ēlābitur, TD. 1, 24, when I drop the book, all assent melts away ([1860]). quicquid fēceris, adprobābō, Fam. 3, 3, 2, no matter what you do, I shall think it well ([1626]). ut quisque istīus animum offenderat, in lautumiās statim coniciēbātur, V. 5, 143, any man that wounded his sensibilities was always flung into the quarries without any ado.