Starting with your cylinders around arbitrary minor axes, your work here is coming along reasonably well, though I do have a few important points to draw to your attention to ensure that you continue getting the most out of this exercise:

• This one's a fairly minor point, but when it comes to those cases where you're pushing your foreshortening towards the dramatic (to that point, you're doing a good job of varying the rates of foreshortening across the set), you tend to always match that with making the cylinder very long on the page. This gives me the impression that you might not be comfortable making that foreshortening dramatic on shorter cylinders (the sort of thing that implies that the cylinder is oriented in such a way that most of its length is relegated to the unseen dimension of depth, rather than being measurable on the page. There's basically two things that changes the rate of foreshortening - there's the nature of the lens we're looking through (whether it's a camera lens, a person's eye, etc), which is applied to everything in a scene equally, and then there's the foreshortening that results from the orientation of a form, which is applied per object, or even per set of parallel edges within a given object, based on how much they're oriented within the depth dimension, versus the two dimensions of the page or canvas itself. You're focusing heavily on the former (the foreshortening that is applied across the whole scene), and may be hesitating from playing with other.

• I am noticing a tendency to hesitate in the execution of your ellipses, especially as they get wider/higher in their degree. It's normal to be concerned about ensuring the accuracy of your marks, but remember that per the principles of markmaking from Lesson 1, we always prioritize the confidence of the stroke. Confidence is a matter of how we choose to approach the problem in the moment, while accuracy will improve with practice, so long as you're making the choice to execute the marks confidently. This will also help you keep your ellipses more evenly shaped, and avoid some of the unevenness that occurs in many of your wider ellipses.

• Lastly, another issue that seems to arise more with the wider ellipses is that the accuracy of your identified minor axes does appear to be less consistent for ellipses with higher degrees, as shown here on 143 and 145. It's not abnormal to have cases where you assume the ellipses are roughly as you intended them to be - but you definitely want to push yourself to always check regardless of what you assume to be true, and to give yourself the time to check as carefully as you can, otherwise it's easy to plateau in your improvement if you aren't catching those mistakes.

That last issue also ends up being the main issue that is present in your cylinders in boxes, which otherwise are moving in the right direction - but I'll speak a bit more on that once I give you a bit of context as to how this exercise is meant to work. 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.

So where you fell short is in that you appear to have entirely skipped the identification of your minor axes altogether. That means that cases where your ellipses are drawn such that they're not aligned correctly are going to be much less useful in assessing the proportions of the box's faces, simply because the contact points are probably a fair bit off from where they would be if the minor axis alignment were more correct. So, without the context of the minor axis being marked out (so we can at least see whether our other extensions are more relevant, or less so), we end up assuming that all of the contact point lines should be taken at face value.

It is unfortunately very important that these error analysis methods are applied in their entirety, as leaving bits out can very easily undermine their effectiveness - kind of like checking a dark room by checking all but one of its corners with a flashlight. Sure it's good to know that those other corners are clear, but it's all kind of moot since the monster is always given somewhere else to hide.

Now, I'm going to assign some limited revisions for this below just to make sure you fully understand how to apply those line extensions correctly. You'll find them listed below.