Elegantiae terminorum

Iam already/now is elegantly used for "then": as "if you have studied the precepts, you will already have learned them." It is also taken for "meanwhile" when joined with vero: as iam vero, that is, meanwhile. It is also taken for "now, now" when doubled: as iamiam. But it is to be noted what follows.
Jamolim and olim iam, diu and iamdiu seem to mean the same, that is, already for a long time. Olim is also taken for the future by the poets. Also sometimes for "at some time," not for iamdudum. Diu means nothing other than "for a long time": as "I navigated for a long time," "I was sick for a long time." But we do not say "I departed for a long time," "I mounted a horse for a long time," but "I departed recently," or "I departed long ago," or "I mounted a horse." One must take care lest verbs that are instantaneous be applied to these adverbs iamdiu and diu, iamolim and olim; wherefore it is not correctly said "iamdiu publicavi opus hoc" I have already for a long time published this work, "iamdiu pejor es" you have been worse for a long time, but iampdudum or iamdudum, which is said of a matter or action that is lingering. Although it is correctly said "iamdiu est opus publicatum" the work has already been published for a long time, because here it signifies the continuation of the time during which the work was published. Hence it is that it is not well said "iamdiu sonuit tuba" the trumpet sounded long ago, "iamdiu mortuus est" he died long ago; but "tuba dudum et iamdudum sonuit," and "dudum mortuus est."

Jamdudum and iamolim, iampdem, iaminde are so said from their simples, namely dudum, olim, pridem, which in these compounds signify continuation; in the simples, however, they do not. Also nuper, dudum, or pridem are said of a matter or action that does not persist but passes instantly. Jamdudum and iampdem are said of a matter or action that is insisted upon and lingers. And those former ones demand verbs of past time. These latter ones more frequently demand the present, although sometimes the past: as "dudum intravi navem" I entered the ship a while ago. But "iamdudum te expecto," that is, an hour or half an hour, or there are two hours or three, or to a great extent I have been waiting for you since I entered and while I am waiting for you. Also "nuper ex Sicilia redii," a long time has passed; the action is not lingering. But "iampdem ex urbe absum" I have been absent from the city for a long time, or "iampdem ex urbe redii," that is, I returned in past days or months. Also "many days are, or many months, since I have been absent from the city." And here continuation of time is signified; there, it is not. Here, it signifies with present lingering; there, the moment of application. Also iamdudum and iampdem are sometimes taken for "continuously" by the poets. Virgil: "Iamdudum sumite poenas" Long since take the penalties. Theocritus: "Iamdudum te amat" He has loved you for a long time, unless it were "solebat" he was accustomed.
Jentari is to eat breakfast original: "iéntaculum" to restore the fasting.
Juventa is an age, but juventus are the youths themselves.
Idem is sometimes taken for etiam also: as "beneficenta eadem liberalitate vocamus" we call beneficence by that same liberality, that is, which also.
Is, ea, id receive that conjunction et. Idem, however, does not: as "rectis pauca et eadem trita," or "eadem detrita" without the conjunction.