The sentence is instructing someone to start by summarizing or stating again the main point or key concept that was learned during a lesson or educational experience. This is likely part of a larger task or assignment where the person needs to reflect on what they have learned and articulate it in their own words. By restating the lesson learned, it helps reinforce the understanding and allows for further discussion or analysis of the topic. To understand the meaning of the sentence, you would need to comprehend the context in which it is being used, such as a classroom setting or a self-reflection activity.