"Romeo and Juliet" contains many instances of dramatic, situational and verbal irony. Even in the Prologue, in an example of dramatic irony, (when the audience knows what the characters do not), the audience is immediately aware that things will not end well with talk of "star-crossed lovers (who) take their life."
In terms of situational irony, a situation exists between the Montagues and Capulets which would prevent any friendship, let alone marriage, between the families. It is expected that the inevitable marriage, albeit forbidden, will ultimately repair the rift and it is not anticipated that it is the deaths of Romeo and Juliet that will be responsible.
In acts IV and V, there have been many developments and Juliet is frantic to prevent a marriage with Paris. In Act IV, scene v, Juliet is presumed dead and Friar Lawrence comes asking if Juliet is "ready to go to church" (33). Verbal irony is present as Capulet responds, "Ready to go, but never to return." The verbal irony exists because the assumption is that she is going to church to get married but in fact is ready (it is assumed) for her funeral. There is also dramatic irony present here because the audience knows that she has taken a potion and is not actually dead.
In Act V, scene i, Romeo has just been told that Juliet is dead and is on his way to see for himself. He says," I will lie with thee tonight," (34), and the audience presumes that the plan will come together and they will start their married life. This is both dramatic irony (the audience knows or thinks it knows what is going on) and situational irony. Romeo intends to buy poison because he thinks Juliet is dead but the situation is not what he thinks it is.
The situation will unravel as miscommunication confuses and causes more unnecessary deaths. The ultimate situational irony exists as the Capulets and Montagues discuss what statue may be appropriate to honor Romeo and Juliet who are "poor sacrifices of our enmity" (V.iii.303). In terms of dramatic irony, the audience always knew that it would be a tragic end for these "star-crossed" lovers.
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