What a summary! It is awesome!
Thanks for sharing your expeirences, essays, and understandings with us. I believe you have wrapped up almost everything a chinese student should know about writing. As a Chinese guy who has spent 4 years in US, I learned the importance of writing in a hard way. Oftentimes you are just one step away from a great job offer, but you screw it up because you don't have a professional writing sample readily available.. Improving writing skills takes time, and requires significant amount of effort and practice. No short-cut but it will benefit you for sure, sooner or later, one way or another.