In Act III of "The Tempest", how does Prospero treat Ferdinand? Why? How is this treatment like and unlike the treatment of Caliban?

In Act Three (not Two), Prospero treats Ferdinand like a slave. There are several reasons for this. He is still angry over the loss of his kingdom, and Ferdinand is linked to that. He (Prospero) is showing his mastery over the island. He's trying to keep control of his daughter…though losing to love. And he's trying to test Ferdinand's character and make him work to demonstrate his love of Miranda. It's a test, like those in fairy tales and myths.

It's like his treatment of Caliban because both must labor for Prospero due to his authority and magic (and both want Miranda). It's unlike because it will end.