1. Most people know what a 16-year-old gymnast looks like.
2. Most people who have been pregnant or have ever known anyone who was pregnant know what a pregnant woman looks like at 7 months, regardless of the strength of her abdominal muscles.
3. Before a musician understands what it feels like to play in tune, the concept of playing in tune remains simply an abstraction. Once a musician understands what it physically feels like, playing in tune becomes a life-long obsession.
4. Items 1 and 2 don't have anything to do with my life.