One major purpose of the thesis is to predict what will follow. It does this for both writer and reader. It provides the writer with purpose and direction throughout the composing process. For the reader it creates expectations about the form and content of what's to come, and the reader's satisfaction with the final essay will depend largely upon whether these expectations have been satisfied.
The beginning and end of your essay are positions of high emphasis. They deserve careful attention. Keep them short and purposeful. Use them to create and satisfy expectations. Get into the habit of reading your introduction and conclusion together, with an eye toward revision, as one of the last stages in your writing process.
The thesis/support pattern refines and systematizes natural thought patterns. Besides offering an organizational framework for your writing, the thesis/support pattern can also serve as an aid to invention. It can help you probe your subject and uncover your thoughts about it. It can also help you see the reasons, experiences, observations, and judgments that underlie those thoughts.
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