The reason why he wants to become a doctor because I like helping others, or someone who is ill and there is no money to maintain, thus becoming a doctor came to take care of sick people, including lokrua of the cross.
The reason I want to be a doctor because I like helping others. Or patients who have no money to maintain. So I want to be a doctor to care for the sick as well as a kitchen with a cross.
The reason why I want to be a doctor because I like to help others. Or ill person and no treatment. So you want to be a doctor to take care of the patient, including cross Lakon, head of him.