Cohesion and coherence 。My car is black. Black English was a controversial subject in the seventies. At seventy most people have retired. To retire means "to put new tires on a vehicle". Some vehicles such as a hovercraft,have no wheels. ·Wheels go round. Cohesion and coherence • My car is black. • Black English was a controversial subject in the seventies. • At seventy most people have retired. • To retire means “to put new tires on a vehicle”. • Some vehicles such as a hovercraft, have no wheels. • Wheels go round