I like Dr. Zhang's class. He speaks in a convoluted way, but he writes important things on the blackboard. He uses slides but those slides are just wordy definitions. He will write down and derive everything from scratch.

He is very very helpful. He will answer all questions during class and he doesn't mind repeating again and again. He is also very available outside the class.

His tests are like this: if you know how to do it, you can probably finish it within 3 or 5 lines; if you don't know how to do it (often this is the case) you will leave it blank. His tests are definitely tricky and require full comprehension of materials, but if you really understand everything, you can definitely do those problems correctly in a short amount of time. I got bombed in the first midterm but I rescued myself in the second midterm and in the final.

Although he left UCLA, I have to say he is one of my favorite math instructor here. I would definitely take classes with him again if he were still here.

I hope this review is helpful to students taking his classes in another school.