Hey there. Thank you. I'm trying to work with as little lines as possible in general because I like those kinds of lines. I'm finding the sensation akin to tightrope walking in a way, like there's my should lifting my whole arm, and then there's the nib making contact. I can really feel it in my arm but if I exhale as I do these lines and slow down at sharper turns I just find the lines become a nice balance of fluid and sort of controlled at the same time. I feel as sort of drag and inertia, by letting the muscles in my arm sort of have a velocity to them instead of like stopping and starting, for curves at least.

As for form intersections... I found that as assignment says, draw them as shapes first, but have a general idea of what is in what. Then, note how different shapes interact with each other, they create different shapes on the surface of the other object. Also I'm really thinking in 3D as this happens. I learnt a lot when doing this so I think I'll go over some objective rules that I found when doing this, as I'm surprised there is no mention, they seem pretty crucial, yet it was very easy to work it out. Sorry if this gets a bit lengthy, but I'm not the best at explaining things concisely.

When two cubes interact, I think this is easiest because they cut into each others surfaces. If you try to imagine two cubes in your mind, meeting each other, two flat surfaces meeting is like a knife cut. I sort of would imagine in my head if two cubes went through each other slowly there'd be a point when they bury into the other's surface. I'd think for each surface separately.

When two spheres interact, I found that when they meet, it's like an oval that is a slice of the union between the two. The way a sphere submerges into a flat surface is essentially very similar, also for a cylinder.

So I find it's all about surface. A flat surface will receive the cross-sectional shape of the other shape, it's like it projects an impression of that in perspective, so you're just placing a cross-sectional line around the applied object along the plane of that surface. If a surface is curved, it's best to think of the surface being cut by that other shape.

So I think of the receiving surface as being the most simplest. I try to select the flat surface as the receiving surface. But if both surfaces are round, then the general rule I use is to draw it as if a flat surface (as oval) is created between the two like said.

If a cube and sphere meets, I will think of each flat surface as an individual receiver of the sphere. Between each edge, this tends to make a 3-shape because each plane is getting a different cut.

Now with cylinders, I did notice that a elongated curved surface has a bit of its own rule to it.

But not really by much. When a cylinder burrows into a surface, the width of the cross-section is just relatively constant, kind of like how a bullet would go through something. Of course a bullet can enter something at an angle, but also the perspective will additionally make things appear at an angle. But I realised that the cylinder, as a sort of long bullet is actually with its own perspective for the impression it gives. So if you think in terms of the cylinder's perspective of entry you'll notice that your own perspective just adds into the angle of the insertion. Also cylinders always apply an oval regardless of the shape, but just be aware because they have a constant width they create a skew based on their angle of entry into the surface like said.

And I tried cones as well. Mostly to note is that when the length of the cylinder or cone meets a curved surface, it kind of looks like it makes a lip around the thing, I thought this was the most counter intuitive. But the difference with a cone is that the cross-section of projection gets smaller or skews away.

And finally, on pyramids, they are just flat surfaces, but bare in mind that when another object receives their impression, their tips come through as triangles for the base, and the spire of the cone acts a lot like a cube corner pressing in.

I think it's may be a good idea to think in terms of these rules, by surface, because I don't want to be locked into using basic geometric shapes, I mean a lot of art is made of complex surface shapes. Those can be broken down into simpler 3D shapes, but ideally I don't want to always think necessarily in terms of the 3D shape and think more in terms of the surface when getting into say living objects.