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interrogative: P. and V. πότε.
indirect or relative: Ar. and P. ὁπότε.
at what hour: Ar. and P. πηνίκα.
indirect or relative: P. and V. ὁπηνίκα.
relative: P. and V. ὅτε, ὡς, ἡνίκα, V. εὖτε, Ar. and V. ὅπως.
after that: P. and V. ἐπεί, ἐπειδή, ἐπήν (with subj.), ἐπειδάν (with subj.), P. ἐπάν (with subj.).