Keep in mind that the 2 weeks limitation is not a deadline - if anything, it's the inverse, to ensure that people are not encouraged to do anything but take as much time as they need to complete the exercises to the best of their ability.

Alrighty, let's take a look at your work. Overall, while you're doing a pretty good job with the main core of this exercise, your linework definitely varies considerably throughout the first section of the challenge. Your marks are certainly executed with confidence, but there are definitely cases where they waver a fair bit, which suggests that you're not always making consistent use of the ghosting method. In turn, this suggests that you may have rushed through chunks of the work, and looking at your dates, you drew at least 69 cylinders in one day which strongly supports that theory. Regardless of what you're drawing, every single mark you draw demands the amount of attention and care that is required to execute it to the best of your ability.

Considering how many cylinders you drew each day, it's actually quite surprising that there are as many as there are which have been drawn quite well. I still would not recommend tearing through an exercise as quickly as this regardless of whether or not you can stay focused for many hours at a time, though. Make sure you're pacing yourself well, and don't forget to adhere to the 50% rule from Lesson 0.

One thing I generally give students the opportunity to identify for themselves is something I'm actually seeing present in your work. That is, the understanding that the shift an ellipse's degree (narrower on the end closer to the viewer and wider on the farther side) and the shift in the ellipse's scale (larger closer to the viewer, smaller for the farther end) are both related to one another, and are both manifestations of the same properties of the cylinder in question. As a cylinder gets longer, the far end gets both wider in degree and smaller in overall scale, and so any situation where the far end gets wider but not smaller, or smaller but not wider, would stand out as looking off. I'm not seeing any of these mistakes in your work, so at the very least, you do demonstrate an underlying grasp of this concept.

Moving onto your cylinders in boxes, I'm much happier with your linework - at least for the boxes themselves. You're back to ghosting consistently and ensuring each line is straight and smooth, but also accurate and well controlled. Some of your ellipses tend to vary a bit more in this regard, but overall they're still quite well done.

A key point about this exercise is that it's not actually about the cylinders. Instead, just like how we use the line extensions in the box challenge to determine whether or not our lines are properly parallel to one another, in this case we add a cylinder to determine whether or not one face pair in a given box are proportionally square. As we work on getting those additional checks to line up properly, we get better and better at constructing boxes that are proportionally square by instinct, which comes in very handy moving forwards.

To this end, you've shown a fair bit of growth and improvement.

So! All in all, while you certainly did rush initially and you should not be looking at the 2 week restriction being some kind of deadline to hit (applying deadlines can be useful in many contexts, but it tends to be harmful when tackling the fundamental concepts covered in Drawabox), you've largely done a pretty good job. As such, I'll go ahead and mark this challenge as complete.