Before I get into the critique, there's one thing that stands out quite a bit here. For some reason, it appears that you chose not to use a ruler and instead opted to freehand all of your lines. While I can understand circumstances making it difficult for some students to get an ellipse guide, rulers are such an ubiquitous thing that opting not to use one can only be the result of an active choice on the student's part. The wrong choice.

When I give allowances as part of the course, it will only ever be because I think those allowances will help students focus on the core of the lesson, instead of wasting their brain power on unimportant elements that are better practiced with some of the rudimentary exercises from earlier in the course. So if you happened to choose not to use a ruler because you felt you'd be able to further practice your freehanded lines, then that's somewhat misguided. After all, if you want practice with freehanded lines, there are way more effective ways to do so, where it can be targeted. You can practice the ghosted lines exercise, ghosted planes, or draw freely rotated boxes. Here, you want your brain to be completely focused on observing your reference images, identifying the forms there, and working out how to build up these complex objects with precision and care.

And of course, if you opted to freehand your lines because you wanted to be impressive, well, that's just hubris and it does no one any good.

Now, moving onto the actual critique, your work is certainly moving in the right direction, but as a whole I think you're falling pretty far short of what you're really capable. I think the ruler thing is one factor, but you also may have underestimated just how much more you could do with each drawing.

The form intersection vehicles are fine - surprisingly a lot of students actually think I'm asking for a lot more than this, but you nailed it well, just arranging a bunch of primitive forms in the likeness of vehicles. When you got into your actual complete vehicle constructions, you skipped a lot of steps, opting to go for more approximation and eyeballing rather than subdividing things to figure out exactly where it all should go.

One example of this is with the coast guard boat. You drew a different one from my own demonstration, but it's still a fairly straightforward comparison to make - and where I subdivided extensively, drew a complete footprint of the boat along the bottom plane, and build it up quite steadily, you did far less, and instead relied on your internal understanding of 3D space to help you make educated guesses throughout.

Now, your grasp of 3D space is strong - that's what this course is designed to develop and train, by rewiring your brain, and obviously it's been doing its job. The problem is that the work you do in this course is not where you demonstrate how well it's developed. Every single drawing here is an exercise of its own, and you continue to develop that understanding by going through all of the steps, tedious though they might be. With every step you skip, you walk away with less.

Your drawings - or perhaps more accurately, your sketches - all look really nice, they're just not what this course is asking of you. You need to slow yourself down, use the tools at your disposal, think through the steps, and build these vehicles up gradually, one step at a time.

While I generally do not like showing other students' work (it is never my intention to pit students against one another), I do find it sometimes necessary in Lesson 7 to show just how much time can be invested in a single one of these drawings. From what I can see here, I don't think any of these drawings took you more than one sitting. There is of course no rule that says you should expect to complete your drawings in a sitting, or in a day, or even in multiple days. All that matters is that you give each drawing as much time as it requires of you.

So, to take that point home, take a look at the work done by veedraws. She was helpful enough to include a little time card showing the staggering number of hours she spent on each study. While I certainly don't expect students to pour quite that much into these, it paints a picture to say the least.

The key thing here is that she isn't any more skillful than you. Your linework is solid, your observational skills are keen, and your grasp of 3D space is very strong. Right now, the distinction is that she is patient, and you are... less so.

I'm going to assign a few pages of revision below, so you can push yourself further to show me the best of which you are capable - which is, of course, your only responsibility as a student of this course.