Final answer:
During the Progressive Era, a concerned citizen can write a letter to a member of Congress expressing their concerns and ideas for reform, such as women's suffrage and workers' compensation.
Step-by-step explanation:
During the Progressive Era, many individuals sought to address social problems and advocate for change. As a concerned citizen living during this time, you can write a letter to a member of Congress expressing your concerns and ideas for reform. For example, you could write about the need for women's suffrage, an eight-hour workday, workers' compensation, or the direct election of U.S. senators. By writing to your representative, you can contribute to the ongoing efforts of the Progressive movement.