Most Master's programs require students to have a minimum score on GRE, which tests verbal, quantitative, and analytical writing skills. If students continue to take courses at the graduate level, a final thesis is required for most Master's programs. Doctoral students take courses until they have earned enough credit hours to attend their qualifying examinations, which are usually taken over several days and often include both a written and oral component. After doctoral students pass their qualifying exams, they are advanced to candidacy and can begin writing their dissertations. Before the degree is given, the completed dissertation must be orally defended before the candidate's faculty committee. To conclude my lecture, we can say that American educational system has its unique characteristics. First, there is no country-level education system or curriculum that exists in the United States. Actually, most of the control of American public schools lies in the hands of local school districts, which can be divided into elementary schools, middle schools, and high schools. Besides, in the United States, education is compulsory for all students until age 16. Finally, we also talked about the admission requirements and the credit hour system of the undergraduate as well as graduate program in American universities.