Dr Ma, please tell us something about blindness.About 285 million people around the world are blind or have other eye problems,mostly in poor areas, and about 80 per cent of these cases can be prevented or cured.However, many people don't have money for medical treatment.How does ORBIS help?ORBIS uses its Flying Eye Hospital to visit poor areas.On the plane, volunteer doctors do operations.The plane is also used as a training centre.Why don't you work in a hospital?Many of our patients can't afford to go to hospital, so we have to go to them.