单选题 The year at an American college is divided into 2 semesters (学期，半学年) or 3 quarters (学期，每学年分3学期制度中的一学期). A semester includes 15 weeks; a quarter includes 10 weeks. American college students usually go to school from September to May. They can also study during the summer.
Students choose their classes a few weeks before the start of each term. Universities offer a great many classes in the students" main area of study and in other areas as well. Students must take both. These include science, maths, computer, history and English. Other classes may be just for fun, like dance, theatre (戏剧) or sports. Tests are usually given in the middle of the term and at the end of it. The final exam is extremely important. In some classes, the professor asks the students to write a research paper (研究论文) or to complete a certain task instead of taking a test.
Classes at an American college are usually organized through lectures. For example, a student may attend 2 or 3 lectures a week by the professor. As many as several hundred students sit at each lecture.