I have an in class essay to write which addresses the question of how themes are developed and explored in Romeo and Juliet with specific reference to the the chorus/opening sonnet and the play as a whole. Could you point me towards good reference material to address this?

In Shakespeare's Romeo and Juliet, the Prologue sets the scene for the theme of love and hate between the two families, the Capulets and the Montagues. We discover that these two families have been feuding because of an "ancient grudge." It appears that this feud has broken out anew and foreshadows the fight between Benvolio and Tybalt in act I. These brawls also foreshadow Romeo's involvement in the feud which leads to his exile after he kills Tybalt later in the play. Through a series of miscommunication, Romeo and Juliet also meet their own fate.
The Prologue also reveals the theme of love between two opposing families when Romeo and Juliet meet and fall desperately in love. They are described as a pair of "star-cross'd lovers." This description, unfortunately, foreshadows their death at the end of the play. Lastly, it is revealed in the Prologue that it is the death of Romeo and Juliet that will end their "parents' strife."
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