Avoid Cliches. There are a few standard reasons why people become doctors, and so it is very easy to fall into cliched expressions and ideas. Though it's fine to express a commonly_held notion, try to find a personal way to express it. For example, rather than write "I want to be a doctor because I want to help people," discuss the ways that you have shown your generosity and kindheartedness in the past; bring specific examples__such as your volunteer experiences__so as to avoid a direct (and possibly cliched) declaration of your point. Sometimes cliches are unavoidable; just make sure your essay isn't full of them.
oMake sure your spelling and grammar and impeccable. If in doubt, consult a dictionary and/ or grammar book or ask someone whose knowledge of English your trust to read this through for you. Alternatively, send your personal statement to Get Into Uni Oxbridge editors http://www.getintouni.com who will edit this for you _ to perfection.