Sanitation workers remove the trash and garbage that people and businesses produce. Increasing amounts of garbage and trash are becoming a problem in our world today.
Many years ago, doctors trained nurses to help them treat people. Today, nurses go to school to learn about medicine and about how to help people when they are sick. Nurses perform many of the same duties as doctors.
Doctors help people stay healthy. When people get sick, doctors help them get well again. Today, doctors use many complex instruments to treat people. Long ago, doctors had few instruments and did not know as many ways to help people get well.