Fucking A, dude you just reminded me of differential equations. it wasn't even a professor but some Chinese grad student. Not only did she not speak English, but she also just wrote all the solutions on the board without explaining to us how she got from A) to solution. At least not that any of us could make out.

Ironically, girls in my class came to me for help, and I ended up getting a C because I did my final project in Mathematica instead of matlab, and, thus, the fucking TAs couldn't understand my work. I refused to rewrite it.