This is VERY far from advanced. Humerus is misspelled as many have pointed out. CalvariUM is singular while calvariA is plural. The "back bone" is a horrible term and I spent most of the allotted time trying to figure what was wanted. Vertebral column or vertebrae would be much better "techinical terms" for the laymans term spine. The sternum isn't the base for ribs either' it's just one attachment for some of the ribs. Vertebral bodies are more properly the bases. I could go on, but I have better things to do with my time.