Starting with your arrows, you're mostly doing a good job of pushing a sense of flow and fluidity to them (with a touch of stiffness/wobbling in that top left one), though you're still not applying perspective to the negative space between the zigzagging sections. Just as the ribbon itself gets narrower as it moves away from the viewer, those gaps should also be compressing, as perspective applies to both the size of objects themselves and the distances between them.

Moving onto your leaves, you've done a good job of capturing a similar sense of flow and fluidity, and as a result have established how those leaves not only sit statically within space, but also how they move through the space they occupy. I can also see that you're making a concerted effort to build your more complex details directly on top of the scaffolding established by the previous phase of construction. My only concern here however is that some of these small lines tend to wobble a lot - as you can see with this one, those edges are extremely wobbly. It's clear that you're entirely capable of drawing smooth lines, so it seems like you made the conscious decision to draw that line to be wobbly. Perhaps the leaf itself had a frayed edge - in which case, approaching it as you did skipped a step. If you want to capture an edge like that, it should be first drawn with a smooth stroke, then the wavering should be added on top of it (like what is shown in the bottom right of this diagram. You've done this more appropriately elsewhere, so perhaps this was just a bad call.

Looking at your branches exercise, I think you're largely moving in the right direction with this. I do think that your ellipses are a bit stiff and uneven at times, and there are a number of cases where you don't draw through them a full two times before lifting your pen (which contributes to the stiffness). For the most part you're extending your line segments fully halfway towards the next ellipse, although not always - there are a number of cases where you extend much less, resulting in less of an overlap between the segments (which really helps create the illusion of a single continuous edge as shown here). Be sure to keep this in mind as you continue practicing this exercise in the future.

Moving onto your plant constructions, for the most part you adhere quite well to the principles of construction. There are a few things I'm going to point out that should help as you continue to move forwards, but all in all you're approaching these constructions quite well.

The first thing I want to mention is that a number of your drawings have been relegated to a smaller portion of the page than they perhaps should have been. When it comes to thinking through the spatial reasoning problems involved in constructional drawing, our brains benefit considerably from being given more room to work. Despite this, it's pretty common for students to start out trying to draw things smaller, and at times in a more cramped fashion. It often comes down to a sense of uncertainty and a lack of confidence that makes the student want to hide their flaws by drawing smaller, when in fact drawing smaller tends to exacerbate those issues. Always try and give your drawings as much time as they require. You by no means have to fit two or three or four drawings to a page. Start with your first drawing, giving it as much room as it needs, and if there's enough room left over after that, you can work in a second. If there isn't, that's fine - one drawing on a page is totally fine, as you've done later on.

I mentioned this above, but it comes up in some of your constructions - draw through all of your ellipses within this course. Outside of the course, I'm not concerned - but you can consider it to be a part of Drawabox. It will help you draw them with a greater sense of confidence and will also help keep your ellipses evenly shaped. Additionally, you only need to do it two full rounds before lifting your pen, and drawing through your ellipses too much can also be a problem you'll want to avoid.

You do this at some points, but neglect to in others - when you construct something cylindrical, like a flower pot or what have you, always construct it around a central minor axis line. This will help you align your ellipses more consistently.

Lastly, always apply the ghosting method to each and every mark you draw. This means planning and preparing beforehand so you can execute your mark with confidence and without any hesitation. Your linework is generally quite confident, although you have a habit of being a little sketchier at times, and you show signs of not necessarily planning as much ahead of time as you should. Definitely avoid situations like the flower pot on this page where you've gone back over lines multiple times with no proper reason.

So! I've pointed out a number of things for you to work on, but I feel you should be good to move on. I'll go ahead and mark this lesson as complete.