Anchor: A group of people riding a bicycle down a street.
Entailed: Bikers moving the the street in a group.
Contradiction: A group of skateboarders rides down the street.
Contradiction: The classical Greek period began as Athens fell precipitously from power.
Contradiction: A barbecue is happening outdoors.
Contradiction: The family is skydiving.
Contradiction: Don't you understand that I was correct?