Starting with your organic forms with contour curves, I can clearly see that you're making an effort to stick to the characteristics of simple sausages here. You are generally having a fair bit of success with this, although continue to keep an eye on the ends' shapes, making sure that they're circular in shape. There are definitely cases where they get more stretched out (like this) and areas where they get more smushed (like this). Also, remember that the degree of your cross-sectional slices - which are what the contour curves themselves represent - should be getting wider as we slide further away from the viewer along the length of the form. If you're unsure as to why that is, you can review the Lesson 1 ellipses video.

Continuing onto the insect constructions, your work here is by and large coming along quite well! I can see a clear focus on working from simple to complex, as per the principles of constructional drawing, and generally avoiding skipping steps to add more complexity than can be supported by the structure that is already present. In addition to this, I can see a great deal of attention being paid to the idea of respecting the forms you put down as though they exist in 3D space, generally avoiding making alterations to them in the 2D space of the page.

That's actually an issue I usually try and impart in my critiques for this lesson, as most students at this stage are prone to jumping back and forth between actions taken in 2D space - that is, just drawing lines on the flat page with all the freedoms that allows us in terms of how we alter or engage with what's already been drawn - and actions taken in 3D space where every form is respected as being three dimensional, and where that impression of the existing structure is further reinforced with every next form that is added.

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.

This is not an issue I really see in your work at all. There are some minor places where you'll add a partial shape (like the spikes on this one's legs which are not closed forms, so we don't get a proper grasp of how they connect to the legs they're attached to. Here you've drawn them as complete shapes, although there's nothing in those silhouettes that actually establishes the connection between the forms either. You can see an example of how those kinds of things can be added such that they connect believably to the existing structure on this lobster claw demo - specifically pay attention to the little "teeth" on the inside of the claw, and how the part of that silhouette that touches the main claw structure actually wraps around it.

So, similarly to those 'teeth', whenever we want to build upon our construction or change something, we can do so by introducing new 3D forms to the structure - 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.

Overall you've done really well with this, and you've shown a lot of attention being paid to the forms you're drawing as they exist in 3D space.

I'm also pleased to see that you have generally stuck to using the sausage method in many regards, with a few minor shifts away from that approach here and there, and some inconsistency in how completely the approach was applied. To start, be sure to apply every part of it, as shown here on the sausage method diagram. Don't forget to define the joint between the sausages with a contour line, for example.

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). I think these diagrams should be helpful in terms of understanding how to build upon those structures, rather than altering their silhouettes.

And that about covers it! I'll go ahead and mark this lesson as complete. Keep up the good work.