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.