I am Sandy Lee, an undergraduate student of the department of Electrical and Computer Engineering. At the beginning of this semester, I registered one of your courses, African Literature and Culture. It is a two-hour course held on every Thursday afternoon. Yesterday, I received a notice from my department that a major course, Computer Principle, would be changed to Thursday afternoon. This major course conspicuously influences my credits and it is every important to me. Unfortunately, I can not study your course this semester.