In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Question: Boron only occurs naturally in compounds with what element? Answer: oxygen
Boron only occurs naturally in compounds with oxygen element.

Question: Early in the development of a human fetus, the skeleton is made entirely of what? Answer: cartilage
Early in the development of a human fetus, the skeleton is made entirely of cartilage.

Question: What are two types of frozen percipitation? Answer: snow and hail

Snow and hail are two types of frozen percipitation.