Introduction (Little résumé of the topic) Body (Explanation) Conclusion Use short synthetic paragraphs. Avoid absolutely the first person "I", and expressions like "I think", "In my opinion", etc. It is obvious that you think, and have opinions. Try to use a quite high linguistic register. I suggest to use expressions as "Furthermore", "on the other hands" while passing from a paragraph to another. It is not too much different from and essay in any other language

Thank you Is more formal thanks, thai Is also very usuale in the American English