Nice work! Starting with your arrows, they're flowing quite nicely through all three dimensions of space, and you've got them moving in a variety of orientations. One thing to keep in mind though that with the bottom of your first page of arrows, you've got an arrow where the spacing between the first zigzag is narrower than the second zigzag. Perspective suggests to us that this spacing should compress more consistently. Unless you have a specific intentional reason, try to stay within what is expected of the basic rules of perspective - in this case, the spacing getting smaller consistently as we look farther back.

Moving onto your organic forms with contour ellipses, you're mostly doing a good job of sticking to the characteristics of simple sausages outlined here, though keep an eye on maintaining ends that are both spherical and equal in size. It's easy to end up stretching them out a little, or having them vary in scale.

One other thing I did notice was that the degree you use for your contour ellipses and curves tends to be pretty arbitrary. The degrees of these contour lines instead should be shifting gradually, getting wider or narrower based on how their orientation relative to the viewer changes depending on where along the form we're looking. As shown here, each cross-section defined by a contour line sits at a different location, and depending on where it is in space, it'll be seen at a different angle by the viewer.

With your texture analyses, you've really nailed exactly what you're meant to pick up with this exercise. You've done an excellent job of focusing on shadow shapes and largely setting lines aside. One minor point though - in your third row, towards the far right of the density gradient, you end up with these individual line segments where you're somewhat "guessing" which shadows would remain as the light source gets dark. If you take a look at the diagram in this section, you'll see that the shadows that last the longest are those formed where multiple forms come together. So in your second row, you got it right - it's those "Y" shapes where edges meet, rather than the individual edges themselves. Where an edge stands alone, it's more likely to get evaporated when beared down upon with direct light.

Regardless, you're still doing very well with this, and it continues to flow into your dissections. Very nice work.

Moving onto your form intersections, I think you definitely improve over the course of these when it comes to drawing each form confidently and consistently such that it feels as a cohesive part of the same scene as the others. One thing I did notice however was that you do have a tendency to draw your boxes with foreshortening that is a bit too dramatic here. This has a tendency to throw off the sense of scale when you've got a lot of forms gathered together. This is explained back in Lesson 1. Also, some of your ellipses tend to come out a little pointy on one end when you try to deal with narrower ones, and when it comes to cylinders, it can be immensely helpful to construct them around a central minor axis line to keep the ends aligned to one another.

One last thing, however - I'm noticing that you don't appear to have made any attempt to figure out the actual intersections between these forms. Now, this is by no means a major aspect of this exercise (it's primarily about being able to draw the forms such that they feel consistent and cohesive within the same space), but I do at least want students to make an attempt at the intersections in order to serve as an introduction to thinking about the spatial relationships between the forms. This is a concept we explore first here, and then develop gradually over the entire course.

Lastly, your organic intersections are coming along well. You're doing a good job of wrapping the forms one another and having them behave in a manner that sells the illusion that they are all interacting in three dimensions.

Before I mark this lesson as complete, I'm going to want you to make one more attempt at the form intersections, specifically to try the intersection lines out. They don't need to be done correctly - they merely need to be attempted.