Diving right in with your form intersections, at this stage in the game we're still not actually at a point where we expect students to nail this exercise perfectly. Technically we never get to that point in the scope of this course, it's more a representation or manifestation in the purest form of the spatial reasoning skills we seek to develop, and more importantly help students to better understand how to continue developing, and so this exercise ends up being a lot of things. A gauge of how things are going, a targeted tool for honing certain aspects of spatial reasoning, and an opportunity to look at those aspects in more isolation than other constructional drawing exercises allow.

As it stands here, you're definitely ahead of what we expect from our students at this stage, which is that they're merely comfortable with those intersections involving flat surfaces, but still uncomfortable and uncertain when rounded surfaces are added to the mix. There's definitely a greater overall degree of comfort with these kinds of spatial relationships being demonstrated here, although ultimately the main thing we push students to focus on when providing feedback at this point is still going to apply to you.

It primarily comes down to thinking about how intersections are the direct result not of memorizable combinations of different kinds of forms, but rather an active, specific, case-by-case interaction between surfaces in 3D space. Flat surfaces, rounded surfaces, surfaces that are flat/straight in one direction but curved in another (like the lengthwise dimension of a cylinder or cone), surfaces that can be curved in many different directions (like spheres, where there are infinite different curvatures, but only certain ones are going to be relevant to a specific intersection). A single intersection can occur across many of these surfaces, but only in pairs - meaning, two at a time, often separated by hard edges where one surface transitions suddenly into another.

This concept is one you do appear to demonstrate to a significant degree, but as noted on this page, there's still room for continued improvement on this front - which again, is totally normal. I ended up writing more than I intended in my scrawl there, but basically it's just noting that if the cylinder identified there were aligned such that it was running parallel to the boxes' planes, you'd have been correct in focusing all of the cylinder's curvature on one plane, and leaving the intersection for the other as a straight line. Since this is not the case however, the curvature gets spread out across both planes.

As to the other corrections, they're all instances where paying attention to the nature of each plane can help us better understand which components are relevant, and ultimately come to a reasonably accurate intersection. This diagram helps to illustrate this (in the sense of how the boxes' planes help us determine which of the sphere's cross-sectional slices are relevant), and also tries to demonstrate a different framing for curved surfaces, as a rounded transition between surfaces where a hard edge transitions suddenly and sharply.

Anyway! Just be sure to keep those ideas in mind as you continue working on this exercise, and they'll come up again in the homework for Lesson 7.

Continuing onto your object constructions, your work here is coming along extremely well, and it's clear that you've approached it in a way that really adheres to and espouses the core principles behind this lesson. That is, you've approached it with a heavy focus on precision, and have made excellent use of the tools we introduce that allow us to increase the precision with which we tackle our constructions.

Precision is often conflated with accuracy, but they're actually two different things (at least insofar as I use the terms here). Where accuracy speaks to how close you were to executing the mark you intended to, precision actually has nothing to do with putting the mark down on the page. It's about the steps you take beforehand to declare those intentions.

So for example, if we look at the ghosting method, when going through the planning phase of a straight line, we can place a start/end point down. This increases the precision of our drawing, by declaring what we intend to do. From there the mark may miss those points, or it may nail them, it may overshoot, or whatever else - but prior to any of that, we have declared our intent, explaining our thought process, and in so doing, ensuring that we ourselves are acting on that clearly defined intent, rather than just putting marks down and then figuring things out as we go.

In our constructions here, we build up precision primarily through the use of the subdivisions. These allow us to meaningfully study the proportions of our intended object in two dimensions with an orthographic study, then apply those same proportions to the object in three dimensions.

You've made a very thorough use of those tools - especially the orthographic plans - to control every aspect of your constructions, and you've put a great deal of effort and more importantly, patience, into applying these as completely as you can. This is clear in every one of your constructions, but most prominent in structures like this one and this, where you were really forced to tangle with a pretty dense forest of lines, but did an excellent job of keeping yourself aware of what was relevant for each mark you added.

I am also pleased to see that you adhered to certain principles that some students are more prone to forgetting or skipping over - like the construction of your mug handle here, which does an excellent job of leveraging our use of chains of straight edges/flat surfaces to build up scaffolding for eventual curves.

Ultimately I'm not actually able to find any points to be especially critical on. You're checking every box, and are applying everything from the lesson as thoroughly as one can. So, I'm left only to mark this lesson as complete. Keep up the fantastic work.