Normally a student would at least attend ______ classes each week.

A．they hate the constant pressure and strain of their study
B．they will then be able to stay longer in the university
C．such positions help them get better jobs
D．such positions are usually well paid

A．their academic record will affect their future careers
B．they are heavily involved in student affairs
C．they have to observe university discipline
D．they want to run for positions of authority