classes:  lecturer. Although I rarely come to class, but there are difficulties to understand, I emailed to ask you, you answered very enthusiastically, there are also demos.  curriculum. Although I rarely come to class, but there are difficulties to understand, I emailed to ask you, you answered very enthusiastically, there are also demos.  facility. Although I rarely come to class, but there are difficulties to understand, I emailed to ask you, you answered very enthusiastically, there are also demos.  general. Although I rarely come to class, but there are difficulties to understand, I emailed to ask you, you answered very enthusiastically, there are also demos.