Life Drawing, A closed pose each male and female

Working with a life model is always a privellage as they are professional and open minded. As I am in progress of practicing the ways of a fine artist, a life model is the biggest help I can get. I am forced to learn the ways around the body that includes proportion, bone structures, posture, colour, light and tone of the human body. In these lessons I am tought to draw in different techniques in order to get use to the human form. These techniques included 2-3 minute drawings of continuous line, using your opposite hand no taking your eye off the model whilst drawing. These were tough tasks to begin with but in the end was for the best as better outcomes were produced through constant analysis.
These are by far my best outcomes. I used charcoal the whole time and I feel that is exactly where I didn't go wrong as I knew I had no choice. I could not achieve what I had wanted in the second sketch as I had a bit of difficulty. For me to learn I focused on what I felt was the easiest part of the body for me and I then repeated drawing it for practice.