Good effort, William. The resolution of the image you uploaded is a little low so I couldn't clearly see your solution. Best to upload a high-res version next time. From what I can make out, it seems you may have misunderstood what the core shadow is. The core shadow is the part of the form shadow that is not receiving reflected light. So if you take the shape of the form shadow and subtract the shape of the reflected light, you are left with the core shadow. Your correctly identified ambient occlusion where the monkey head touches the table / surface, but have you perhaps missed it in other places? Think especially about gaps and creases, like those found between eye balls sockets.

Nice work. The reflected light (A) on the piggy bank is very strong. However, reflected light is still part of the shadow family. Perhaps this is what you were hoping to clarify by redrawing the terminator in yellow? The choice of a wristwatch was perhaps a little too challenging for this exercise, mainly because of the complexity of the object and the fact that it contains both translucent and very reflective surfaces. We will be dealing with those types of surfaces later in the course. For now, simple objects, with a light colour and matte surface, work best for terminator studies.

Good work, William. For this exercise it works best to make the the form shadow and cast shadow a little closer to each other in tonal value. Also, have a look at the photography tips in this module - uploading good photos, especially for the more advanced assignments, will help us see your work more clearly.