Starting with your ellipses around arbitrary minor axes, I'm pleased to see that you carefully and fastidiously identified all of your "true" minor axes afterwards, in order to help you determine how to adjust your approach as you move forward through the challenge. You also demonstrated pretty good execution of your lines.

Your ellipses were a little visibly loose through the whole thing, with some ellipses coming off a little sloppy. Overall it wasn't too rough, but I do want to remind you to execute your ellipses using the ghosting method, from your shoulder. It looks like you may have forgotten the importance of this, and it could be hurting the results.

Through the first chunk of these, you definitely stuck to the same rate of foreshortening (in fact towards the beginning you were applying virtually no foreshortening, seeming to try and keep the side edges parallel on the page, which of course is incorrect). I did notice however that as you moved forward, you did play with more dramatic foreshortening, but I still do want to reiterate that it's important in these kinds of exercises to vary things like foreshortening, orientation in 3D space, etc. when you're drawing a lot of a simple kind of form.

Now, when you played with more dramatic foreshortening, you did tend to make a notable mistake. Foreshortening is not just reflected in the overall size of the ellipses, with the far one being smaller than the closer one. That is one aspect of foreshortening, but as the foreshortening gets more dramatic, the degree of the far end is also going to get wider. Both the shift in overall scale and the shift in degree goes hand in hand. You'll never end up in a situation where the far end gets smaller, but doesn't get comparatively wider, or vice versa.

Moving onto the cylinders in boxes, while I'm very happy with how you drew the boxes themselves, you don't appear to have entirely followed the instructions for this exercise. From what I can see, your line extensions include those of the box (like from the box challenge), and the minor axis line of the cylinder - but I'm not seeing any of the lines defined by the 'contact points' of each ellipse, as explained here. This means that you were not actively checking if the ellipses' line extensions aligned to the box's vanishing points, and therefore whether the ellipses actually represented circles in 3D space, which is at the core of this exercise.

This exercise ultimately helps us develop our ability to construct boxes that feature two opposite faces that are proportionally square - determining whether how far off we are from having the ellipses represent circles in 3D space also tells us the same about how far we're off from those faces containing them being square. Without checking for this, there was nothing to help inform the adjustment in how you were drawing your boxes, and so you ended up aiming for an entirely different target when doing this exercise.

This is stressed not only in the written material, but also in the video for this exercise, so I'm guessing that while you may have watched/read it, you perhaps did so at the beginning of the challenge and not when jumping into this exercise. That is a bad mistake to make - you should always revisit the instructions of an exercise immediately before starting it.

As such, I'll be assigning some revisions for you to work through below.