To write a thesis statement is to make a claim and outline how you are going to support that claim throughout the rest of the research paper. The thesis statement should be clearly stated in the first paragraph of the research paper.
A thesis statement should be one sentence long and illustrate what the research paper will explain or argue. It should come at the end of the introductory paragraph, and it should include exactly what will be explained in the body paragraphs of the paper. The thesis statement needs to be focused, and it should be narrowed down to what the research paper is specifically about rather than a broad overview of a topic.
Before writing the thesis statement, it is important to know exactly what you want to discuss or prove in the paper. Once you know the claim that you want to make, decide what details of that claim you are going to explore in your research and include that in the thesis. The statement should not be written as an opinion, but rather as a statement that will be further explained and debated. The statement should inspire interest in the reader and persuade them to read the rest of the text.