How to make drawing layer partially in front and partially behind

Hello guys been using toon boom

i am learning and want to know how to put the drawing layer partially behiind a object and partially in front.
i know that if u want to keep something in front u can put the layer on top. but in this case the chair is different object
just look at this picture and tell me
how his hand partially behind and partially infront of chair.
i m newbie.
pls help it would be really nice of u

You can’t have a drawing partially behind and partially on top of another. You would normally separate layers when you need a part on top of another element or you can use a mask to delete part of the drawing and make it appear it is behind. Another solution, at least for traditional animation, is to draw only over the element but that normally is not a perfect solution because over several frames you might notice imperfections. If a drawing is not moving during a shot you can just delete it perfectly to match the layer that’s below.

You can also use Z space to put something in front or behind.
In a single drawing, separate the forearm and the arm in different art layers
Copy and paste this drawing node (they will share the same information)
rename one to forearm and the other to arm
in the properties of the forearm go to drawing tab
You can check or uncheck art layers visibility
uncheck all the layers you dont want
Do the same thing with the arm
then, with a peg in the forearm you can move it in Z axis to put them in front

https://i.imgur.com/2dPsgTq.gif

file exemple
https://www.dropbox.com/s/gay4z96xknl2zi1/arm_rig_exemple.rar