Starting with your cylinders around arbitrary minor axes, for the most part you've handled this well, but there are a couple things I want to call out to your attention, so you can be mindful of them going forward.

• Always remember that every mark we freehand should be applying the three stages of the ghosting method, to ensure that we invest all of our time into the planning and preparation phases, and execute with confidence to avoid wobbling or hesitation. For the most part I noticed hesitation in the execution of your ellipses (with ellipses it's also extra important to engage your whole arm from the shoulder), although upon closer inspection I did notice a touch of wavering in your straight edges as well. It's not abnormal for students to get a little lax at applying the ghosting method as strictly as they should, especially at this stage, so this challenge serves as a good reminder to be mindful and hyper-intentional of every choice we make, and every step we apply throughout the process of making our marks. Students get used to thinking that they're applying the ghosting method, but gradually they shift away from investing their time into the first two steps, and compensate by taking more time to execute... and before you know it, we think we're applying the ghosting method but aren't actually adhering to any of its principles. So, give yourself a quick refresher and take a bit more time with each mark to ensure you're going through the correct steps.

• I noticed later into the set, in cases like 78, 80, 84, 86, 92, 95, and so forth that you started falling into the trap of pushing your vanishing points to infinity. Be sure to review these reminders which explain why this is incorrect.

Aside from that, I'm pleased to see that you're checking the alignment of your minor axes quite fastidiously, and that you're catching both the more obvious and more easily noticed discrepancies, as well as those that are small enough to be easily overlooked.

Continuing onto your cylinders in boxes, by and large this appears to be coming along quite well. 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.

There is one area where your approach is running into an issue, and it comes down to identifying the correct minor axes of your ellipses. Here on a couple examples I've marked out the actual minor axes for your ellipses - as you'll note, your analysis had them as having been pretty much correct. When we have all of these line extensions all over the place, it's easy to slip up and just assume that they are correct, without paying closer attention to the ellipse itself, and in turn. Fortunately, this tends to be more of an issue when the box's proportions are so far off that the actual minor axis veers off in a completely different direction. Our brain thinks, well we can't have made a mistake that bad, and instead resolves that we were just a little off, or that the alignment is correct. In other words, it's easier to identify the true minor axis when it's not too far off, because that's what your brain is looking for.

In order to avoid these assumptions, we have to always be extra attentive to what we're doing - similarly to being attentive to applying the ghosting method in its entirety, as discussed earlier. On top of that, using different colours for the different directions of line extension (or at the very least ensuring that those expected to run down the length of the cylinder, including the minor axis line be drawn with a separate colour) can help us avoid situations where we correctly identify that the minor axis went off and coincided with a totally different set of lines, but don't notice that this is a problem because it aligned very closely with that other set of lines (so for example, if on 201 we'd identified the minor axis of the farther ellipse correctly, we might still not immediately notice that it was that far off, if we assumed it was supposed to be part of the lines going downwards - colour coding can help make the mistake more obvious).

Anyway, all in all, you're headed in the right direction. I'll go ahead and mark this challenge as complete, just be sure to continue working on the points I raised in your warmups.