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.

Example Input: Question: Knees and elbows are examples of what part of the skeletal system? Answer: joints
Example Output: Knees and elbows are examples of the joints of the skeletal system.

Example Input: Question: What part is written first when naming an ionic compound? Answer: cation
Example Output: When naming an ionic compound, the cation is written first.

Example Input: Question: What type of friction is friction that acts on objects when they are sliding over a surface? Answer: sliding friction
Example Output:
Sliding friction is friction that acts on objects when they are sliding over a surface.