Just your average stroll in the park

Jon decided to test his new body-part-swapping power in the park. He got there, and decided to just stoll around until he found a few good candidates. There was plenty to choose from. Jon just needed to decide on who. There was a girl who was playing fetch with her dog. There was the teen couple making out near the bathroom. There was a group of girls trying to study and a bunch of football Jocks who were disrupting them. There were a group of kids having a birthday party. There was several teenage rowboaters who were getting ready for a race in the lake. And there was the old coulple who were feeding the birds. Jon wondered who to swap first and who would be able to recognize that a swap had occured.