Alrighty, let's jump right in. To start, your form intersections are by and large demonstrating a solid grasp of how these different forms relate to one another in 3D space, but I have one quick suggestion - don't draw the intersection lines themselves in a different colour, or with a different pen. I understand that since I used red in the demonstration to draw students' attention to the lines that were being added as we moved one step to the next, but the reason I recommend drawing those intersection lines in black rather than red here is that it reminds us that the intersections are a physical element in the scene - not part of some extraneous analysis of the results. The intersection lines themselves exist like "weld lines" we get when we fuse one piece of metal to another using a torch. Understanding that they're a physical part of the scene can help a great deal when students struggle to understand how intersections work.

Of course, you don't appear to be struggling much at all. While your work isn't perfect (I've marked out a few issues here), it is progressing very well by and large.

Continuing onto your object constructions, as a whole you have worked through this lesson pretty well, but I do have a number of suggestions to offer. Before we get into that, I am very pleased with the level of precision you've employed throughout many of your constructions here - specifically those where you took the time to build out orthographic studies, analyze proportions with two dimensional subdivisions, then apply them to your 3D constructions. Precision itself comes down to the steps we take to declare our intentions, and to declare what information they're based upon. Putting marks down randomly is imprecise, even if they fall where we ourselves intended them to. It is by first declaring that intent - just like putting the start and end points down in the ghosting method's planning phase - that we increase the precision of the final result. Here, we take that further, through the use of subdivision to identify exactly where along the length of an object a particular element should sit.

In that regard, you've largely done a pretty good job. By your own admission you neglected some proportional studies when they would have been helpful, and I expect you'll have learned from that - but I can see that you clearly understand the overall principles of working with precision.

So, here are the points I want you to keep in mind as you move forwards:

• It appears that in your drawings here, you worked with different pens - a ballpoint for laying down the subdivisions, and then a fineliner for actually drawing the object itself. This is unfortunately something I specifically ask students not to do, in the section where I give permission to use ballpoint and other tools. What I don't want students to fall into is thinking of the constructional scaffolding as being separate from the final drawing. That's an easier manner of thinking to fall into here compared to earlier lessons, where the lines were more blurred between final result and the steps we took to get there. Here we actually have the bounding box that gets subdivided - but as a whole, you should still continue to see the whole thing as a sort of sculpture, where you start big and gradually chip away at pieces in three dimensions, whittling it down towards that target result. The additional benefit is that it keeps students from needlessly tracing back over their existing linework, which itself contributes to more hesitant, less confident linework.

• As explained here, try not to jump right into curves. Instead, start out with more straight edges and boxy forms, then round out those sharp corners with smaller curves that adhere more tightly to the existing structure. Here's the jist of what I mean.

• Given our restrictive toolset (which limits us to working strictly in solid black and solid white), we simply don't really have the means by which to capture certain information. For example - local/surface colour. So, filling in things that are dark or black in surface colour as you did here actually makes the drawing more visually confusing. Instead, it's best to reserve those filled black shapes for cast shadows only.

Aside from that, you are doing a pretty solid job, and I think you should be good to continue on. I'll go ahead and mark this lesson as complete.