A red truck is parked next to a burning blue building while a man in a green vest runs toward it.
The red truck is a fire truck.
The color of the truck doesn't automatically make it a fire truck. It is parked next to a burning building, but it could be a pickup truck that belongs to one of the building's tenants.
Just because a red truck is parked next to a burning blue building while a man in a green vest runs toward it dos not mean it is a fire truck.
Not all red trucks are fire trucks.