Starting with your organic forms with contour curves, you're handling this pretty well, although there's a big improvement from the first page to the second, for a fairly subtle reason - on the first page you're sticking to the same degree for your contour lines as we slide along the length of a given sausage, but in the second page you are correctly making it just a little bit wider as we move further away from the viewer. This is correct, and it helps make the sausages feel a lot less stiff. Good on you for sticking very closely to the characteristics of simple sausages as well.

One quick correction though - that ellipse at the end of the sausages (which you should be drawing through two full times) needs to more closely match the degree of the contour curve preceding it. Right now you tend to make them all much more circular.

Continuing onto your insect constructions, there's a lot you've done well here, especially in terms of approaching your constructions with a focus on building from simple to complex. That said, there is some advice I can offer that will help you make the most out of these kinds of exercises.

Firstly, let's talk about the difference between taking actions in 2D space (where we're really just thinking about making marks on a flat page) andtaking actions in 3D space (where we're actually considering how every new mark we put down changes something in 3D space, respecting and reinforcing the 3D nature of the forms that are already present).

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.

Now in all fairness you actually don't seem to cut into the silhouettes of your forms at all, at least from what I could see (there may be some small instances I didn't catch, but overall, good work on that), but there are places where you'll add partial shapes, one-off strokes, or otherwise two dimensional information without establishing how it is meant to exist in 3D space, how it connects to the existing 3D structures, etc. There are a lot of small such cases with all the little spikes and protrusions on this beetle's tusks and legs, though those are more minor issues. Conversely, on this beetle I highlighted that area that comes up from the thorax. Technically, like the mass that wraps around the abdomen, you've added a separate mass to the thorax that incorporates this big protrusion, but in doing so you're simply adding way too much complexity all at once, and it results in the structure feeling quite flat.

Instead of taking actions in 2D space (or in this case adding a too-compelx form), whenever we want to build upon our construction or change something, we can do so by introducing new simple 3D forms to the structure, one by one - forms with their own fully self-enclosed silhouettes - 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.

This is all part of accepting that everything we draw is 3D, and therefore needs to be treated as such in order for the viewer to believe in that lie.

You can see this in practice in this beetle horn demo, as well as in this ant head demo. You can also see some good examples of this in the lobster and shrimp demos on the informal demos page. As I've been pushing this concept more recently, it hasn't been fully integrated into the lesson material yet (it will be when the overhaul reaches Lesson 4). Until then, those submitting for official critiques basically get a preview of what is to come.

Now the only other point I wanted to raise is that while you're applying the sausage method to a point, you're neglecting to define the joints between the sausage segments, as explained in the middle of this diagram. As a whole, the key to keep in mind here is that the sausage method is not about capturing the legs precisely as they are - it is about laying in a base structure or armature that captures both the solidity and the gestural flow of a limb in equal measure, where the majority of other techniques lean too far to one side, either looking solid and stiff or gestural but flat. Once in place, we can then build on top of this base structure with more additional forms as shown here, here, in this ant leg, and even here in the context of a dog's leg (because this technique is still to be used throughout the next lesson as well). Just make sure you start out with the sausages, precisely as the steps are laid out in that diagram.

And that about covers it! I'll go ahead and mark this lesson as complete. While the points I've raised are things I want you to address, you'll have ample opportunity to do so throughout the next lesson. Just be sure to keep it in mind as you tackle your work going forward.