Well it is a little small. A 1369 word essay is a bit on the small side. You can easily elaborate on more points or go into some research about the play. You will be rewarded marks for extra research, something your classmates won't have
. It may also help to give a background of the time, what was the message of the play, why did Shakespeare write it. When I wrote my Macbeth essay I add to mention the history of James I, and why it was based in Scotland etc.
I think you have your hopes way too high for that high B. Shakespeare is hard, and I wrote double that length and only scraped a B out of it.
Also you will get better marks if your work is unique in the some way. May be use a developed writing style. Again I think you are thinking GCSE's are easy. Yes, understanding them is easy, but you need to learn how to get your brain on paper.
This may help:
http://en.wikipedia.org/wiki/Romeo_and_Juliet
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