[1] The main idea should be established in the introductory paragraph of a scientific essay.
-> In almost every essay type, your introduction is <em>introducing</em> your topic. You want to bring up the main idea right away.
[2] The main idea should be restated in the conclusion of the essay.
-> You want to bring up your main idea again. This does many things, it not only reminds the readers what they read, but helps to make sure your essay comes full circle and everything is supporting that <em>one</em> main idea.
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- Heather
