I've my essays corrected by some teachers, and they've given me some useful advice. As my strategy, I start and close my essay using almost the same sentences. For example, "Some say that...., others say that..... I believe, however, that...." and "In conclusion, (repeating my thesis) " Some teachers say these sentenses are basic expressions for essays, but others pointed out that these sentenses are quite predectable and even boring. That's why I've been trying to make more creative ones in my first 'general sentense' in introduction. However, it's sometimes difficult to come up with good sentenses. At this moment, I use my basic 'strategy' sentenses to write. Anyway, writing essay is really tough and I can't improve my writing skill within such a short term. Yet writing essay will be helpful to prepare for the secondary exam: the interview test. So I assume that examinee should practice writing essay more and more before the test.