I think it boils down to asking yourself why an artist MIGHT choose to use a certain line. It could be because it is a high or low contrast area, or the thing carries a lot of weight or doesn't, or the details of something need to be highlighted while others aren't necessary, or a bunch of other different reasons. There's so many possibilities and so many decisions to be made. When you sit down and start one of these study sessions, I think the first thing you should is take the piece and physically put it far away from you. What do you notice about the lines? Which ones pop out and which are faded? In Stan's previous lessons, he had a focus on hierarchy AND light and shadow. Glen Keane probably made the hair darker where he did in order to separate it from the rest of the body and also to bring one of the back locks a little bit closer to the viewport. The areas beneath the feet or hands are darker because they would cast a bit of a shadow on the branch and because they also would stand out from the branch. The knee, lower back, bottom of the right forearm, and the right arm are all dark because they could be a.) hard places or (in my opinion more likely) places with a lot of tension and weight. Even Tarzan's eyebrow is darker because it is furrowed and full of tension. So, it looks like Glen used most of the concepts, which Stan showed us previously, in a variety of ways. Maybe he made this piece to explore how Tarzan moves, or sits in his environment, or to design his character, or something else like that. I'm not sure. I think if you keep experimenting and practicing while keeping those things in mind then you'll start to intuitively do it. I hope this helps,

Wow. This is a very nice drawing.

Woah, so good

Great job!!

this looks so good :O

You have some fine points down. I would recommend trying to replicate the texture of Jeff Watts's lines. Perhaps that means to switch to another paper, but for me, it's always satisfying getting that exact texture down.

You have a good attempt here. I would suggest try to commit to spot the changes in line weight Jeff Watts employs in the skull. It will add more dynamism to your drawing, especially around the outside contours.

Nice work. Jeff Watt's uses soft yet thick lines within the forms. Try tilting your pencil more to get those thicker lines, or use a pencil that has more graphite exposed.

You made yourself something that sounds like a really fun exercise :D Make an attempt at Tetsuo Hara drawings too, and post your work :D I see some of the lines that are very close to the master's drawing, like on the jaw and some of the shading, keep up!

Cool, great study, I think its great that you're practicing his lines, and rlly trying to figure out how the lines are made, good job, keep going :D

I should also say the sheer breadth and quality of Watts' lines themselves, irrespective of the medium 🙂 I have a long way to go.

Really nice work! I love this piece, too

Good first attempt. I'd suggest capturing more of the gestural lines within the hair and body. The original sketch isn't made up of many straights apart from the face.