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Based on vs. Based upon?
My history teacher recently returned a writing assignment to our class, and upon receiving my paper, I noticed that she had marked a word choice error on my paper in the following sentence:
“Plato, Socrates’ favorite and most successful pupil, based much of his work upon his mentor.”, with the word “upon” circled. When I asked her about it, she said that the word should have been “on”.
From an academic standpoint, which is more correct to use in a formal writing assignment? Is one more formal than the other? Do they have the same meaning?
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