What should always be included in an example of a formal writing?

An example of formal writing should always include a clear thesis statement that outlines the main argument or purpose of the piece. It should also utilize proper grammar, punctuation, and vocabulary appropriate for the audience and subject matter. Additionally, formal writing should be organized into coherent paragraphs that support the thesis with evidence or analysis. Finally, citations should be included for any sources referenced to maintain credibility and avoid plagiarism.