The document provides tips for using sentence variety to improve writing. It discusses using simple, compound, and complex sentences. For a grade of C or higher, writers should use all of the sentence structures discussed. To earn higher grades, writers can also manipulate sentence structures to control the pace and tone of their writing. The document provides examples and rules for different sentence types, such as simple sentences containing one idea, compound sentences joining two ideas, and complex sentences adding extra information or using connecting words and punctuation.