Dear Zea, If I were you, I would focus on giving specific examples. The purpose of the independent writing section is to see how you can use the English language. You do not get points for trying to use long sentences with conjunctions or academic words (TOEFL is not an academic exam, it is a level test designed to test all levels of English from elementary to advanced) The raters who mark your exam really wanted to be presented with an essay that they at first understand clearly and then they will look at your use of English grammar and vocabulary. If you look at the example essay that I gave above by an ex-student of mine you will notice that she hasn't used anything overly complicated. She has, however, presented a clear argument using the language that she is comfortable using. If I remember correctly, she in fact got 4 points on the real exam too.