Hips Practice 01

As the hips are the primary focus, they appear comfortably accurate, reasonable for your own subtle artstyle. A sensible technique, comparing the proportion of the hips to other body parts such as the thighs, waist and especially the shoulders. However, on #5, the lines branching from the lower back across the hips stand out to me; they pronounce the bend too much. Try cutting those a fraction whenever making a similar pose and angle, see if it's a better, worse or neutral result not only in accordance to aesthetics, but also what feels right for you and your artstyle.

All in all, it's a very well-done sketch. I hope this critique helps, what little it contains, as there isn't too much to go off a sketch and I'm not an avid artist myself..