The document provides guidance on how to write an effective thesis statement. It defines a thesis statement as a complete sentence that contains the main idea of an essay. It should state an opinion or attitude, rather than just announcing the topic. It is typically located at the end of the introductory paragraph and informs the reader of what to expect in the rest of the essay. It may also include subtopics to signal how the essay will be organized. The thesis statement is the controlling idea for the entire essay.