Hello Mujin249, I'll be the teaching assistant handling your lesson 4 critique.

Starting with your organic forms you're doing a pretty good job of sticking to the characteristics of simple sausages that are introduced here.

There is some subtle wavering to some of your linework in this exercise, which that suggests that as your pen touches the page you may be hesitating as you execute the line. This usually happens because the student is worried about making a mistake and being less accurate - but as noted in Lesson 1's principles of markmaking, the confident execution is our top priority. I notice signs of hesitation have been called out in your previous critiques, so I think perhaps you might find it helpful to read through this comment from Uncomfortable, where he talks more about how we use the ghosting method to tackle hesitation.

I noticed a couple of places such as this where you placed an ellipse on an end of the sausage that the contour curves tell us is facing away from the viewer. Remember that these ellipses are no different from the contour curves, in that they're all just contour lines running along the surface of the form. It's just that when the tip faces the viewer, we can see all the way around the surface, resulting in a full ellipse rather than just a partial curve. But, in this case if the end is pointing away from us, there would be no ellipse at all. Take a look at this breakdown of the different ways in which our contour lines can change the way in which the sausage is perceived - note how the contour curves and the ellipses are always consistent, giving the same impression of which ends are facing towards the viewer and which are facing away.

Most of your contour curves are sticking to a similar degree. Keep in mind that the degree of your contour lines should be shifting wider as we slide along the sausage form, moving farther away from the viewer. This is also influenced by the way in which the sausages themselves turn in space, but farther = wider is a good rule of thumb to follow. If you're unsure as to why that is, review the Lesson 1 ellipses video.

Moving on to your insect constructions your linework generally appears more confident here, as the wobbles become less frequent, which is good progress. As for the constructions themselves, you're doing an excellent job. You're starting your constructions with simple solid forms, and (usually) building things up through the addition of new forms. You're doing very well at defining how all these pieces fit together by using a contour line where they connect, helping to reinforce the solidity of your constructions.

So, overall your constructions are really sold, though I did spot a few places where you'd added a quick bit of complexity with a one-off line or a flat partial shape, not quite providing enough information for the viewer to understand how the addition is supposed to connect to the existing structures in 3D space, and as a result this reminds the viewer (and you) that the drawing is a series of lines on a flat piece of paper. I've marked a couple of examples in blue on one of the legs of your grasshopper, and shown how we might build these additions up as complete new forms here.

Because we're drawing on a flat piece of paper, we have a lot of freedom to make whatever marks we choose, but many of those marks would 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 the various types of actions we can take on a construction using the example of a sphere in this diagram, and while building organic constructions in this course we'd like you to stick to taking actions by adding in 3D, as shown in the lower right.

So, when we want to build on our construction or alter something we add new 3D forms to the existing structure. Forms with their own complete 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 something you're frequently doing very well! I can share a couple of extra examples not yet featured on the lesson pages with this beetle horn demo, as well as in this ant head demo. As Uncomfortable has 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.

The next thing I wanted to talk about is leg construction. I'm happy to see that you've stuck with the sausage method, and that you're doing a great job constructing chains of simple sausage forms and defining how they connect together by drawing a contour curve at each joint.

It is good to see that you've been exploring building onto many of your sausage armatures to create a more characteristic construction of the legs of these insects. I've got some diagrams and demos to share with you which I think will help you to build onto your leg constructions more effectively in the next lesson.

• Here see how we can break a larger engulfing form into separate pieces so that each one's silhouette will make ample contact with the existing structure.

• These diagrams show examples of building onto existing structures with 3D forms instead of flat shapes or one-off lines.

• This ant leg demo shows how this approach can be pushed further to capture all sorts of lumps, bumps and complexity that we might see in these kinds of structures.

• Finally this dog leg demo shows an example of how this approach can be applied to animal constructions. This is pertinent, as we'd like students to stick to the sausage method of leg construction throughout lesson 5 too.

So! All in all, great work. I'll go ahead and mark this lesson as complete.