[1864.] (1.) The indicative imperfect is regularly used with cum, when, to denote a continued action parallel and coincident in duration with another continued action, also in the imperfect: as,
quom pugnābant maxumē, ego tum fugiēbam maxumē, Pl. Am. 199, while they were fighting hardest, then I was running hardest. tum cum rem habēbās, quaesticulus tē faciēbat attentiōrem, Fam. 9, 16, 7, as long as you were a man of substance, the fun of making money made you a little close.
[1865.] (2.) The indicative imperfect is often used with cum, when, denoting a continued action, to date an apodosis in the perfect: as,
legiōnēs quom pugnābant maxumē, quid in tabernāclō fēcistī? Pl. Am. 427, what did’st thou in the tent what time the legions fought their mightiest? hīs librīs adnumerandī sunt sex dē rē pūblicā, quōs tum scrīpsimus cum gubernācula rē̆ī pūblicae tenēbāmus, Div. 2, 3, to these books are to be added the six On the State, which I wrote at the time I was holding the helm of state. But when the object of the clause is not distinctly to date the apodosis, its verb is in the subjunctive ([1872]).
[1866.] (3.) The indicative perfect or present of vivid narration is used with cum, when, to date an apodosis in the perfect or present of vivid narration: as,
‘per tuās statuās’ vērō cum dīxit, vehementius rīsimus, DO. 2, 242, but when he uttered the words ‘by your statues’ we burst into a louder laugh. cum occīditur Sex. Rōscius, ibīdem fuērunt, RA. 120, when Roscius was murdered, they were on the spot. cum diēs vēnit, causā ipse prō sē dictā, damnātur, L. 4, 44, 10, when the day of the trial came, he spoke in his own defence and was condemned. The present is particularly common in old colloquial Latin: as, vivom, quom abīmus, līquimus, Pl. Cap. 282, we left him alive when we came away. For cum prīmum in narration, see [1925]; for cum extemplō, [1926].
[1867.] (4.) The indicative perfect or present of vivid narration is regularly used with cum, when, to denote a momentary action when the apodosis denotes continued action: as,
cum Caesar in Galliam vēnit, alterīus factiōnis prīncipēs erant Aeduī, alterīus Sēquanī, 6, 12, 1, when Caesar came to Gaul, the leaders of one party were the Aeduans, of the other the Sequanians. eō cum veniō, praetor quiēscēbat, V. 4, 32, when I got there, the praetor was taking a nap.
[1868.] An emphatic indicative clause with cum, while, often follows the main action.
The clause with cum is usually inconsistent with the main action, and cum is often attended by intereā, interim, all the time, etiam tum, still, nōndum, hauddum, not yet, no longer, quidem, by the way, or tamen, nihilōminus, nevertheless: as,