Today's class is a pre for teachers based on the PPT we made, which is a simulation rehearsal, and the purpose is to show better results when we actually provide solutions to Party A. I am responsible for who, and after the pre was completed, the teacher gave us valuable advice, among which the most impressive advice to me is not to put all your words on the ppt, it should be brief, but at the same time, it should not be omitted very much. Therefore, it is very important for the audience to see what is easy to understand the text, attached to our explanation.