Starting with your cylinders around arbitrary minor axes, unfortunately there is a significant issue that stands out immediately - you appear to be drawing all of your cylinders specifically with no convergence of those side edges, as though the vanishing point that governs them is at infinity, in the manner discussed back in Lesson 1.

This is problematic on two fronts. The lesser of these is that the instructions specifically stated to vary the rate of foreshortening, as shown here in the assignment section (in bold). It is extremely important that you take more care in following the instructions to the letter.

The bigger issue however is that eliminating the convergences altogether is incorrect in the context of perspective. In effect, you've specifically forced the vanishing point to infinity, but we are not in direct control of where our vanishing point falls - not directly, anyway. What we control is the intended orientation of the form in 3D space, and it is this which dictates where the vanishing point falls. In this challenge, like the box challenge, we're effectively rotating our forms arbitrarily in 3D space.

The vanishing point will only actually go to infinity when the set of edges in question (those governed by whichever vanishing point we're talking about) are aligned perpendicularly to the viewer's angle of sight - basically not slanting towards or away from them through the depth of the scene. Since we are indeed rotating our forms arbitrarily, the chances of having things line up so perfectly are slim enough to be ignored, so there should really be at least some convergence (even if only slightly) in those side edges.

Fortunately we aren't seeing this issue in your cylinders in boxes - here you've done a pretty solid job. 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.

In applying the line extensions correctly and consistently throughout the set, you've allowed yourself to identify where your approach could be adjusted to bring those lines' convergences together, and ultimately improve your underlying grasp of those boxes' proportions.

Now, unfortunately before I can mark this challenge as complete, you are going to have to address the fact that the first section was done incorrectly - but once that's sorted, you should be well armed to jump into Lesson 6.