:v I need more pencils, one is not enough

To draw the pear given in the assignment page, I first layered out an outline, which simplified the shape of the pear with straight lines. Afterwards, I identified and drew the shadows of the pear by dividing them into two groups (as according to instructions): lighter shadows and dark shadows. Again, I followed the instructions and divided the light into three groups; it appears that I made some of the surface in the "light" a tad too dark. It also looks smeared like tomato sauce on pizza dough. I used my index finger to make the light more gradient. However, that might of have been a mistake. Somehow, I made the edges on the left side of the pear soft, and the edges on the right side of the pear sharp. Also, I included too much of the lower right corner in the shadow. The shadow there should of have been extremely small. The shadow on the left side of the pear needs to be smaller; also, in the middle, I should have included an oval-shaped protrusion incurred by light into the shadow; thereby making it look more similar to the pear given in the assignment model. What do you think?