Critical Thinking Questions Why is it important for a speaker to include supporting material in a presentation? Why do different types of supporting materials work better in different situations. Give an example. How can a speaker use statistics as supporting material in a presentation? How can a speaker use a personal experience as supporting material in a speech? What should the speaker be cautious about when using personal experiences? Before deciding to use a specific piece of supporting material, a speaker needs to evaluate the material to determine that it is appropriate for the speech and audience. How should a speaker go through this process of evaluation?