Honestly, I disagree - I feel your line confidence throughout this challenge is quite good. I don't see any cases of hesitation or uncertainty. Sure, you may struggle in some aspects of accuracy, and in getting those ellipses to touch all four edges as intended, but the confidence itself which is our top priority, you're doing very well. The rest will continue to fall into place with practice.

Jumping straight into your cylinders around arbitrary minor axes, I feel your work here is quite well done. You're demonstrating a good deal of care in the execution of your marks, and you're incorporating a pretty good spread of orientations, rates of foreshortening, and so on. You're fastidious in checking your ellipse alignments, and I can see a good deal of growth over the course of this part of the challenge. Lastly, I am getting a general sense that you understand how the shift in scale and the shift in degree from one end of the cylinder to the other work in tandem to convey how much the cylinder is being foreshortened (whereas some students will apply them independently, incorrectly allowing for dramatic shift in scale but a relatively minimal change in degree).

Continuing onto your cylinders in boxes, most students don't entirely pick up on the true nature of this challenge - but it seems that you certainly have. You are spot on - the exercise isn't about the cylinders, it's all about the boxes themselves, and developing students' instincts in regards to drawing boxes that feature two opposite faces which are proportionally square. It doesn't quite extend to drawing a full cube just yet, but it is a step in that direction.

By adding the ellipses, and their own line extensions to the mix of error analysis, we're able to identify how far off we are from having those ellipses represent circles in 3D space, and therefore how far off we are from having the faces that enclose them represent squares.

Throughout this part of the challenge, your linework has continued to remain consistent and accurate, although as you mentioned you do sometimes end up with gaps between the ellipse and one or two of the face's edges. As long as your intent is to fit that ellipse snugly within the plane however, I am not concerned with these discrepancies. Furthermore, as you worked through the challenge, I can see the proportions of your boxes fall more and more within the range of "good enough" as far as representing boxes with square ends, regardless of how they're oriented in space. This should serve you well throughout the next lesson - so, I'll go ahead and mark this challenge as complete.