ἄνω ποταμῶν ἱερῶν χωροῦσι παγαί → the springs of sacred rivers flow upward, backward to their sources flow the streams of holy rivers
return: P. and V. ἐπανέρχεσθαι, ἀνέρχεσθαι.
happen: P. and V. γίγνομαι, γίγνεσθαι.
revolve: P. περιφέρεσθαι.