[2360.] Indicating change of subject, ille is this other man. In such cases it is often best expressed in English by a proper name or a descriptive word.
ad sē adulēscentem iussit venīre. at ille, ut ingressus est, cōnfestim gladium dēstrīnxit, Off. 3, 112, he gave orders to admit the young man. But this other, the moment he entered, drew his sword. rūsticus expectat dum dēfluat amnis: at ille lābitur et lābētur, H. E. 1, 2, 42, he is a peasant waiting for the river to go down: but the river flows and will flow on.
[2361.] In concessions, ille often precedes quidem; in translation no pronoun is required.
librī scrīptī incōnsīderātē ab optimīs illīs quidem virīs, sed nōn satis ērudītīs, TD. 1, 6, books rashly written by men respectable enough but of insufficient education. est tarda illa medicīna, sed tamen magna, TD. 3, 35, it is a powerful remedy, though slow in its working. hīc, is, and iste are used rarely in this way.
[2362.] In poetry ille may serve: (1.) To repeat a thing with emphasis: as,
arma virumque canō Trōiae quī prīmus ab ōrīs Ītaliam vēnit, multum ille et terrīs iactātus et altō, V. 1, 1, arms and the man I sing, from Troja’s shore the first to come to Italy, much tossed that man by land and sea.
[2363.] (2.) To emphasize the second of two ideas: as,
nunc dextrā ingemināns ictūs, nunc ille sinistrā, V. 5, 457, now with his right redoubling blows, now mighty with his left. nōn tamen Euryalī, non ille oblītus amōrum, V. 5, 334, still not Euryalus forgetting, no, not he his love!
[2364.] (3.) As a provisional subject, to anticipate the real subject, and keep the attention in suspense till the real subject comes with emphasis: as,
ac velut ille canum morsū dē montibus altīs āctus aper substitit, V. 10, 707, and e’en as he, goaded by bite of hounds from mountains high, the boar hath paused.