Hi @Romain Decotte, nice drawings! They seem pretty accurate and I think you're showing the form quite well. - Try to make the abs conform more to the ribcage. 1st image top drawing: In the reference the abs angle in slightly, as if they were completing the egg shape of the ribcage. 2nd image top drawing: Same as above. The abs aren't showing the roundness of the ribcage as they do in the reference. 2nd image right drawing: The abs on the compressed side are pushed out by the ribcage making a cylindrical form, you could have more of this in your drawing. - I feel like the attachments in some of these are a little vague. In the 2nd image, top drawing, it feels a little like you´re not sure where the pubic crest is. The lower portion feels a little like it's floating. In the 3rd image, top drawing, you seem to not have found the insertion on the ribcage. Visually, the top pair of abs seem to stop at the thoracic arch, but they actually continue up slightly to insert on the ribcage. This is hard to see, but making a mental note of this, or drawing the abs very lightly all the way to the insertion, could be a good idea when studying anatomy. To sum up: Bones first, & find the attachments. I think it will help to think of the abs as a series of planes. Hope this helps :)