In Romeo and Juliet, what is an example that makes the claim that the drama is a story about tragic love?
The tragedy of Romeo and Juliet is foretold in the Prologue to Act I of Shakepeare's play. Indeed, there are three phrases which indicate the tragic nature of the love between the children of mortal foes:
From forth the fatal loins of these two foes
A pair of star-cross'd lovers take their life;
Whose misadventur'd piteous overthrows
Doth, with their death, bury their parents’ strife.
The fearful passage of their death-mark'd love,...
Is now the two hours' traffic of our stage...(1.1.5-12)
The Prologue states that the "star-cross'd lovers" are marked by fate, while a series of ill-fated events keep them from communicating and being with each other--"misadventur'd piteous overthrows"--and the play elaborates on this situation, the fated love, "their death-mark'd love," in the following two hours.
Two other passages that comment upon the tragic nature of the love of Romeo and Juliet are found in the final act, Act V, as the Prince chides the Capulets and the Montagues:
See what a scourge is laid upon your hate
That Heaven finds means to kill your joys with love....(5.3.303-304)
and he closes the play with these sorrowful remarks,
A glooming peace this morning with it brings.
The sun for sorrow will not show his head.
Go hence, to have more talk of these sad things;
Some shall be pardon'd, and some punished;
For never was a story of more woe
Than this of Juliet and her Romeo. (5.3.317-322)
Romeo and Juliet are tragic hero and heroine because they are of noble stature, and through a series of fated events, they are brought to a final downfall because of errors in judgment and inexplicable outside forces that overwhelm the two lovers.