Overall, your work here is looking pretty good. There is certainly still room for improvement, but this will continue to come with practice. The key thing to keep in mind is that your approach should always be focused on thinking about how your lines are oriented in order to have them converge consistently towards their shared vanishing point. Since we're not using concrete VPs right on the page, it requires us to balance several lines in our mind at a time.

When drawing a line as part of a box, we usually do so in relation to other existing lines. Often students will try and draw a line in relation to the other marks with which it may share a corner, or those with which it may share a plane. Instead, there are only 4 lines you should be thinking of at any given point, and all others can largely be ignored. Those lines are the one you're drawing, and the other three with which it shares a vanishing point. Not all of these lines will have been drawn, so of those you may have some that are committed on the page, and others that have not yet been pinned down - so in our minds, we can play with the orientation if this second group, in order to figure out where they should all be converging to.

As we think about this, it helps also to consider the angles at which all these four lines leave their implied vanishing point. Often (though not always) the two middle lines of a given set will have a very small angle between them. By the time they reach the box itself, this angle can become so insignificant that they may as well be running parallel to one another - a relationship that is an extremely useful hint we can take advantage of. This explanation is obviously a bit confusing, so it is also explained in this diagram.

So, in your work I can see that you're generally demonstrating a good sense for these convergences, but that there are some cases where you end up thinking more in terms of lines that share a plane (which can result in lines converging in pairs, like the red and blue lines for the box at the top right of this page (numbering definitely would have helped for the sake of identification, but oh well).

So, I've outlined some things to think about when drawing these kinds of freely rotated boxes in the future - and I encourage you to incorporate them into your regular warmup routines, along with the exercises from lesson 1. I'll go ahead and mark this challenge as complete.