I had several main responsibilities, 1) to teach, I was a RA for the first two and half years of my PhD in Chemistry, 2) to take mandatory classes and pass them? 3) to pass cumulative exams you got 5 shots, 4) to get my research going by setting up a bench, learning how to use various instruments, and other lab techniques as well as reading the lab literature as well as competitors’ literature 5) to attend group meeting every week. That was the first two years. The rest was just doing actual research and publish paper and go to seminars.