Editing is an important part of the writing process. Once your document is fairly well-developed, you need to edit. While your instructors may prize thoughtful argument, rich description, and thorough research, they are also likely to value careful editing.
Editing involves making "local" changes--that is, changes at the sentence and word level as opposed to "global" or large-scale changes, such as deleting the first three pages of a four-page document. Editors typically reread their texts word-by-word and sentence-by-sentence, while considering stylistic principles as well as grammatical, punctuation, and mechanical errors. When editing, writers trim down overblown phrases and replace inexact words, among other things.
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