Complex sentence: Lussurioso, the Duke's heir by his first marriage, has asked him if he can find a procurer to obtain a young virgin he lusts after; the brothers decide that Vindice will undertake this role in disguise, to give an opportunity for their revenge.
Split into simpler sentences: Lussurioso, the Duke's heir by his first marriage, has asked him if he can find a procurer to obtain a young virgin he lusts after. The brothers decide that Vindice will undertake this role in disguise, to give an opportunity for their revenge.