A.T. Robertson Commentary Luke 8:9

"And his disciples asked him what this parable might be." — Luke 8:9 (ASV)

Asked (επηρωτων). Imperfect of επερωταω (επ and ερωταω) where Mr 4:10 has ηρωτων (uncompounded imperfect), both the tense and the use of επ indicate eager and repeated questions on the part of the disciples, perhaps dimly perceiving a possible reflection on their own growth.

What this parable might be (τις αυτη ειη η παραβολη). A mistranslation, What this parable was (or meant). The optative ειη is merely due to indirect discourse, changing the indicative εστιν (is) of the direct question to the optative ειη of the indirect, a change entirely with the writer or speaker and without any change of meaning (Robertson, Grammar, pp. 1043f.).