Start with an intro...
And then discuss, explain, analyse, justify, comment on the pros and cons. (In different paragraphs, preferably).
Marks are given for two-faced discussion. Both advantages and disadvantages.
And in your conclusion, evaluate/ justify clearly your point of view, with reasonable arguments. Balance both the sides of your discussion and make a judgement based on the relative importance of the pros and cons, or the elements identified.
The main difference between an English essay and an Economic one is that your point of view and judgement in an Economic essay must imperatively be given at the END of your essay, after evaluating ALL your arguments.
Marks are separated for Identification, Knowledge & Understanding, Analysis (within the context), Evaluation & Clear justification.
Check out for words like: Describe, analyse critically, how far do you agree, evaluate, ....
And when evaluating, these may help: On the light of the above discussions, on a more balanced argument, on a final basis...
Why don't you check the mark schemes? It'll help you.
