If you've read my task 1 lessons, you'll know that I always write 4 paragraphs:
1. Introduction - paraphrase the question
2. Overview - describe 2 main or general things
Let's forget the introduction and overview for the moment, and focus on the two 'details' paragraphs. Why do we need two paragraphs?
The answer is that this encourages you to divide the information into 2 groups, and hopefully this means that your essay will be better organised and you'll make some useful comparisons.
Click here to see 3 pie charts (taken from Cambridge book 8). Thinking about the 'details' paragraphs only, how would you divide the information into 2 groups?