Many teachers believe that the responsibilities for learning lie with students. 1 a long reading assignment is given, instructors expect students to be familiar with the information in the reading even if they do not discuss it in class or take an examination. 2 students are considered to be those who are motivated to learn for the sake of 3 , not those interested only in getting high grades. Sometimes homework is returned 4 brief written comments but without grades. Even if grades are not given, students are responsible for learning the material assigned. When research tasks are 5 , professors expect students to take it actively and to complete it with minimum guidance. It is students' responsibility to find books, magazines, and articles in the library. Professors do not have the time to explain 6 a university library works; they expect students, particularly graduate students to be able to exhaust the reference 7 in the library. Professors will help students who need it, but prefer that their students not be 8 dependent on them. In the United States, professors have many other duties besides teaching, such as administrative or research work. 9 , the time that a professor can spend with a student outside of class is limited. If students have problems with classroom work, they should either 10 professors during office hours or make appointments.