Starting with your organic forms with contour curves, you've done a good job of sticking to the characteristics of simple sausages - or closely enough to make it clear that you were aware of that requirement, and actively working towards it. There are little discrepancies here and there, but that's totally normal and expected. What's important is your intent. Your contour curves are also quite smooth and confidently drawn - definitely more accurate on the second page rather than the first (likely because you took more time on that one compared to the first). As a whole, good work.

I have just one quick point to draw to your attention - make sure you pay attention to the "degree shift" on the contour lines, as we slide along the length of the sausage away from the viewer. You're doing this to an extent, and in some cases - but there are many where your contour curves maintain a more consistent degree throughout. I suspect you know why, though if you're unsure, you can reference the Lesson 1 ellipses video.

Continuing onto your insect constructions, in almost every way here, you're doing a fantastic job. Most importantly, the vast majority of your drawings demonstrate a strong understanding of the difference between engaging with your constructions as though they exist in a real, believable, three dimensional space, and engaging with them as a collection of lines and shapes on a flat page. This is incredibly important, and while there are a few cases where you take some shortcuts by jumping back in 2D space (undermining some elements of that solidity in doing so), overall you're doing very well.

Because we're drawing on a flat piece of paper, we have a lot of freedom to make whatever marks we choose - it just so happens that the majority of those marks will contradict the illusion you're trying to create and remind the viewer that they're just looking at a series of lines on a flat piece of paper. In order to avoid this and stick only to the marks that reinforce the illusion we're creating, we can force ourselves to adhere to certain rules as we build up our constructions. Rules that respect the solidity of our construction.

For example - once you've put a form down on the page, do not attempt to alter its silhouette. Its silhouette is just a shape on the page which represents the form we're drawing, but its connection to that form is entirely based on its current shape. If you change that shape, you won't alter the form it represents - you'll just break the connection, leaving yourself with a flat shape. We can see this most easily in this example of what happens when we cut back into the silhouette of a form.

In this drawing of yours, I've highlighted a few different areas. In red, there are situations where you've established a larger form (like the initial head, thoracic and abdominal masses), then decided that it didn't quite match your reference, so you cut back into them at a later point. In blue are the few cases where you extended out those existing silhouettes or attempt to build onto them with flat/partial shapes.

Instead, whenever we want to build upon our construction or change something, we can do so by introducing new 3D forms to the structure, and by establishing how those forms either connect or relate to what's already present in our 3D scene. We can do this either by defining the intersection between them with contour lines (like in lesson 2's form intersections exercise), or by wrapping the silhouette of the new form around the existing structure as shown here.

You can see this in practice in this beetle horn demo, as well as in this ant head demo. You can also see this stressed quite heavily in the more recent shrimp and lobster demos, which focus heavily on the idea that every step needs to establish its forms as solid and tangible, so that everything that follows can then continue to respect that understanding.

Ultimately you understand most of this already - it's just that it may be a more instinctual or nascent understanding that is not fully established, and so my hope is that by going over it in specifics here, it'll kick it up to the next level for you.

Another point I did notice was that when building on top of your legs' sausage structures (which largely do a good job of adhering to the specific requirements of the sausage method here), you're doing a great job of not only respecting the fact that the approach is all about laying in a base structure or armature that captures both the solidity and the gestural flow of a limb in equal measure. When you actually build upon those structures, you even do so with a fair bit of regard for these "additive constructional" principles, although I have two main recommendations on this front.

Firstly, if you find yourself drawing a sausage and then widening it through its entire length, that's a sign that the original sausage probably should have been thicker. This isn't always the case - sometimes the ends being smaller is important, and thus starting with a skinnier sausage is the right call - but it is something to keep in mind.

Secondly, I can see a lot of cases where you basically end up wrapping the whole thing in a larger form, leaving the contact between the addition and the existing structure to only exist at the ends. While this is by no means incorrect, the more limited relationship this establishes between the levels of construction is not ideal, and often separating them into separate pieces as shown here can be preferable, as it allows for far more contact between the silhouette of each individual structure and the sausage underneath.

This idea of building up the bulk through the addition of smaller elements can also help us to achieve the impression of more complex organic structures - like musculature, which is useful in the next lesson. Here's the same concept at play with an ant's leg, and with a dog's leg. Of course, the specifics of how we build up these forms varies on a case by case basis, with the reference image being the main source of information.

So! As a whole, you're doing a great job. I'll go ahead and mark this lesson as complete.