Expository essay For this paper, you will write an expository essay that compares the predictions made in the 2019 report with the 2021 report and persuasively argue to your readers why the overall predictions for the future have changed or have remained the same. Expository essays are ones where you “investigate an idea, evaluate evidence, expound on the idea, and set forth an argument concerning that idea in a clear and concise manner” (Purdue University, 2021, para.