I'm starting with one negative so I can get it over with at the start: You don't have confident and smooth lines. This is a problem that is seen in all of your pages. It's clear that you draw every line in parts, breaking them up into small chunks and leading them off from each other. This makes all of your lines look rigid and lifeless. You need to draw all the lines from your shoulder, not taking your pen off the page until the end of the line is reached. It appears as though you're trying too hard to make every line look perfect, which makes it instead look worse than it would if you sped up. You need to keep your arm loose, but your hand firm. I hope I've made myself clear, but see these notes for more: https://imgur.com/a/uMsS1UG

Now...

Your arrows are looking quite good. You've done a good job of changing the spacing and the width of the arrows as they move through space and you seem to have a solid understanding of how they flow in 3D space. This is exceptionally well demonstrated in your top and middle-right arrows. You need to work on your hatching though. The hatching closest to the fold should be really clumped up and they should slowly space out as they move away. Another, very minor point on then back ends of your arrows: try to think of the arrows as strips of paper. The paper can't bend in the same plane it occupies, it can only bend over itself. A few of your arrows bend in impossible ways, so think carefully about the direction your arrows bend in space.

Your understanding of 3D space really comes though again in your leaves and branches. They are incredibly well constructed and it is clear you grasp the methods explained in the lesson well. Extra edge detail is done well too, making sure not to zig-zag across and instead treat each new detail as it's own form. When placing contour lines on your leaves, try observing real leaves' veins. Most of the time, they aren't perfectly straight as you've drawn them, but instead dip in close to the center stem and curve out as they move away. Implementing this will help to sell the illlusion that these are leaves floating in 3D space and not lines on a page. You have a lot of sharp turns in your branches, but at these points you skimp out on your contour ellipses. Instead of placing just one ellipse, try placing two or more to really flesh out those curves. This will also help you to draw more confident lines from the shoulder.

As is the theme of this critique, your understanding of 3D space and your ability to construct plants are excellent. All of your plants look mostly three dimensional and believable. So, lets take a look at what you can work on: In your ferns, aloe vera and sunflower, you don't draw through your forms in places where it is crucial to do so. In all three, where you have drawn leaves or petals that sit behind another leaf or petal, you have not drawn though, showing where it connects to the main plant. This makes them look like they are floating behind the plant, or are actually attached to the other leaves. I can understand the fear of drawing through, as they make the entire image a lot less appealing, but that is not what we are here for. We are here to create ugly drawings that accurately represent 3D space, and to do that, drawing through is necessary. It's also important that you remember to draw the spheres around the points at which your branching stems connect, as without this, your leaves on the sunflower look flat.