Starting with your arrows, you're off to a great start - the linework here is extremely confident, and sells an excellent sense of fluidity with which the arrows push through all three dimensions of space. This carries over very nicely into your leaves, where you're not only capturing how they sit firmly in 3D space, but also how they move through the space they occupy. I'm also very pleased to see that you're doing a great job in building up edge detail on your leaves' silhouettes, through the addition of individual strokes, adjusting that silhouette one bump at a time.

Continuing onto your branches, your work here is coming along quite well. I'm seeing appropriate shifting to your ellipses' degrees, and you're extending each edge segment fully halfway to the next ellipse, allowing for a healthy overlap from one segment to the next. There are two quick things I want to suggest, however:

• When drawing the next segment, instead of drawing it where the previous one ought to have been, try to use the last chunk of the previous segment as a runway, overlapping it directly before shooting off towards your next target as shown here. This will no doubt make things a bit harder, but it'll also allow you to learn more directly from your previous mistakes.

• Be sure to draw through all of your freehanded ellipses two full times before lifting your pen, as discussed back in Lesson 1. You do this to a point, but you often fall short at 1.5 turns or less.

Moving onto your plant constructions, to be completely honest, you've knocked this lesson out of the park. You're showing excellent attention to constructional principles, building everything up step by step, and drawing through all of your forms to demonstrate a great deal of respect for the solidity of the forms with which you're working. Since I don't really have a whole lot more of value to offer, I think it's only fair that I acquiesce to your request of a demonstration of that coral cactus - though to be honest, I don't know where you found this completely absurd plant. Looking at it kind of makes my skin crawl.

I should mention, however, that this one in particular does kind of push the principles of the lesson to their limits, in a sense. That's not inherently an issue - Drawabox isn't about teaching you how to draw all plants, all insects, all animals, or all cars - or really, any of them. Rather, it's about performing the same exercise time and time again, starting from simple pieces and gradually building up to something more complex, while every step of the way considering the relationships between the 3D structures we add to our construction, and how they relate in space to that which already exists. It's simply a puzzle, and in the solving of it, we train our brain to better develop its own internal model of 3D space.

So, long story short - the way I approach this one will be a little less formulaic, and you should not be concerned that you were not able to figure out how to go about it.

Here's how I'd go about it. The main thing I'm keeping in mind here is that the way I'm starting out the cactus' head has two distinct faces to it. There's the main triangular area, but then along the tip there's a "top" face to give it thickness and dimension. To this, I add 'wings' on either side, with the same top face/front face split. From there, it's primarily a matter of implying the presence of those weird protruding forms by inventing the shadows I feel they ought to cast (when it comes to texture my focus is always on understanding the nature of the forms themselves, rather than strictly reproducing the shadows that are present there - if I understand the forms, I can use them to create whatever shadow patterns at whatever density I need in a given location).

The texture is still the most annoying part, but it's also the least important. What matters is primarily establishing the thickness of the cactus' head, so you can distinguish the parts along the top from the rest along the sides.

So! I hope that helped. Anyway, as I said, you really did a great job with this lesson and should be proud of what you've accomplished. I'll go ahead and mark this lesson as complete, so keep up the fantastic work.