Starting with your cylinders around arbitrary minor axes, there are two main points I want to call out. The first of these is that the instructions, specifically in the assignment section, requests that students include lots of variety in their rates of foreshortening across this first set. It seems that across a significant number of your cylinders here, you specifically eliminated the foreshortening altogether by making the side edges run parallel to one another as though the vanishing point towards which they were converging were "infinite" in the manner described in Lesson 1.

As you pushed further into the set, you certainly did include some variety in your rate of foreshortening, but the vast majority still appear to neglect foreshortening altogether. I won't hypothesize as to the reasoning of this (although I encourage you to reflect on why the instruction to vary foreshortening wasn't heeded at first), but I do want to stress that in addition to this, in this challenge eliminating the foreshortening altogether (and generally forcing vanishing points to infinity) is actually incorrect.

We don't control where our vanishing points go - not directly, anyway. We control the desired orientation for the form, we're drawing, and therefore the orientation of each set of edges that make up the given form, but it's the orientation of those sets of edges which dictate where the vanishing point that governs them will fall. There is a fairly limited set of orientations that will result in a set of edges' vanishing point being pushed to infinity. It only happens when those edges are running perpendicularly to the viewer's angle of sight, just running across their field of view without slanting towards or away from them through the depth of the scene.

Given the fact that we're rotating our forms randomly here, just as we did in the box challenge, the chances of our cylinders aligning to the viewer so perfectly is slim enough that we can pretty much say it's not going to happen, and always incorporate some convergence to those side edges, whether slight and gradual (in the case of more shallow foreshortening), or rapid (in the case of dramatic foreshortening).

Now the other point I wanted to call out in regards to this section is that your line work shows signs that you perhaps didn't invest as much time into it as you could have. More specifically, it doesn't appear that you're applying the distinct stages of the ghosting method to your linework (neither to your straight edges nor to your ellipses), as is required for all of the marks we freehand throughout this course. You certainly are executing your marks with confidence, but without the appropriate planning and preparation beforehand, you tend to run into issues that could be avoided with the investment of more time - as is your responsibility, per what is explained here in Lesson 0 (in the sense of giving yourself all the time you require to do the work to the best of your current ability).

Additionally, I'm noticing a tendency not to draw through your ellipses two full times before lifting your pen - you tend to stop at one and a half turns.

Continuing onto the cylinders in boxes, your work here is certainly better. This exercise is really all about helping develop students' understanding of how to construct boxes which feature two opposite faces which are proportionally square, regardless of how the form is oriented in space. We do this not by memorizing every possible configuration, but rather by continuing to develop your subconscious understanding of space through repetition, and through analysis (by way of the line extensions).

Where the box challenge's line extensions helped to develop a stronger sense of how to achieve more consistent convergences in our lines, here we add three more lines for each ellipse: the minor axis, and the two contact point lines. In checking how far off these are from converging towards the box's own vanishing points, we can see how far off we were from having the ellipse represent a circle in 3D space, and in turn how far off we were from having the plane that encloses it from representing a square.

My only concern here is that the looseness of your ellipses can at times make the error-checking a little less effective (in that you're left guessing a lot more about where the contact points actually are). While this is to a point unavoidable, do be sure to give yourself more time when executing these ellipses to ensure that you're working with the most helpful data you can.

Before I mark this challenge as complete, I will be requesting revisions relating to the first section. You'll find them assigned below.