G1620–ἐκτίθημι–ektithēmi

and when he was cast out, Pharaoh's daughter took him up, and nourished him for her own son.

ἐκτεθέντος ektethentos “When was being exposed”

But Peter began, and expounded [supplied: the matter] unto them in order, saying,

ἐξετίθετο exetitheto “he was explaining [it]”

and he began to speak boldly in the synagogue. But when Priscilla and Aquila heard him, they took him unto them, and expounded unto him the way of God more accurately.

ἐξέθεντο exethento “they expounded”

And when they had appointed him a day, they came to him into his lodging in great number; to whom he expounded [supplied: the matter,] testifying the kingdom of God, and persuading them concerning Jesus, both from the law of Moses and from the prophets, from morning till evening.

ἐξετίθετο exetitheto “he was expounding”