classes:  lecturer. High-quality side students that the machine room does not provide enough machines (because the machine is broken or does not install the program).  curriculum. High-quality side students that the machine room does not provide enough machines (because the machine is broken or does not install the program).  facility. High-quality side students that the machine room does not provide enough machines (because the machine is broken or does not install the program).  general. High-quality side students that the machine room does not provide enough machines (because the machine is broken or does not install the program).