Hi Lingxiao,  good work here with a subtle, quiet story.  I liked seeing how you used and interpreted the poses from class and made them meaningful to your story.  When im looking at your process (the three page progression of your sketching process) I see a good “sketching” in the first page, so you can use the poses, and in the second page a little more info so the compositions make sense narratively.  however, moving from the second to the third page, I see very little further development of forms – a good example of this is the legs- little more than stick figure legs in the second page, and I still see those same stick figure legs in the third, but now they are draped with fabric.  if you cut this corner, skip this step of developing form, how can you get better at understanding form?  anatomy? Structure?  lighting?  etc… its kind of tough to see that last portrait in the last panel and not see a glabella established or even tried, even though it was central to the 2.5 hour demo I did on head construction.  In conclusion, it seems to me that the sketching process here skips from very generic, very skechy and unresolved right to finish without a good attempt at resolving the issues, which leaves the final result a little undernourished.