Starting with your arrows, you're doing a great job here. You've nailed the sense of fluidity and flow of each arrow, and explore the full depth of the space of your scene, applying perspective to both the positive space (the width of the arrows) and the negative space (the distance between the zigzagging sections).

Your organic forms with contour lines are similarly well done. You've stuck to simple sausage forms with minimal complexity, helping maintain the illusion of solidity and form. One thing that isn't entirely there however is the natural shift in degree for your contour ellipses and contour curves, as we move along the length of a given sausage form. I can see a shift in some, but for most it appears to remain fairly consistent. The degree should be changing naturally, widening or getting narrower, as the orientation of that circular cross-section changes relative to the direction the viewer is facing.

You absolutely nailed the texture analyses in a way that I don't often see from students at this stage, given that the exercise is an introduction to the concepts of observational drawing and the use of cast shadows rather than outlines. I'm especially pleased with your leaf study, as this is something students don't quite grasp without a fair bit of difficulty, usually seeing the veins of a leaf as simple branching line rather than actual forms. Your use of cast shadows is excellent, and you're doing a great job of covering the full range of densities. This carries over into your dissections quite nicely.

As is the theme with this submission, your form intersections are coming along great. Your forms feel consistent and cohesive within the same space, and the intersections themselves are demonstrating a very well developed grasp of space and the relationships between forms within that three dimensional space. While this exercise is merely intended to be an introduction to the concept, to be developed upon throughout all the lessons til the end of this course, you've definitely come in with an advantage of experience.

One minor point I want to mention is that I can see a tendency to reinforce some of your lines in a manner that appears more automatic or instinctual, where you've gone back over a line without the planning/forethought of the ghosting method (as would be used when adding line weight). This isn't a good habit to feed, so try and force yourself just to put one mark down at a time, always applying the ghosting method for every individual stroke.

Lastly, your organic intersections are coming along well, selling the illusion that these forms exist within three dimensions, piling and stacking on top of one another as they look for a state of equilibrium instead of appearing as just a series of flat shapes pasted on top of one another. If I had to call out one thing, it'd be just to take a little more time thinking about how the cast shadows wrap around the surfaces upon which they're being projected - you're doing fairly well at this already, but I suspect it's an area where you may want to invest a little more time to really meet your potential.

I'll go ahead and mark this lesson as complete. Keep up the great work.