So I'm reading Visual Complex Analysis by Tristan Needham. It's a beautiful book that's not very hard to understand at all; however, I just don't know if I have sufficiently learned what I'm supposed to learn. Hell, sometimes I'm not even sure what I'm supposed to take away from it. In my humble opinion, the exercises do not, a lot of times, test my knowledge. At least not directly.
I think this is happening because all the books I've read so far had: a summary, an objective list for each chapter and section, and exercises dedicated to each section that are very straight forward. I'm trying to find ways to do it on my own, like sketching transformations, finding geometry proofs to do using complex numbers, etc...
Still I feel that a lot of times what I've learned won't stay in my long term memory since it wasn't solidified by exercises and problems.
PS: I have nothing against the exercises in the book, because just like the author stated, they're very interesting and fun to do.