A listener at Hefei University of Technology in Anhui Province, China, has a question for our Foreign Student Series. The question involves the system of job names in American higher education. Zhang Xiang wants to know the difference between positions like professor, associate professor and lecturer.

In the United States, a person who wants to do research and teach at a college or university usually has a doctorate, the highest degree. But sometimes a school may offer positions to people who have not yet finished their doctorate.

Such a person would be called an instructor until the degree has been completed. After that, the instructor could become an assistant professor. Assistant professors do not have tenure.

A person with tenure cannot be easily dismissed. Such appointments are permanent. University teachers and researchers who are hired with the understanding that they will seek tenure are said to be on a tenure track. Assistant professor is the first job on this path.

Assistant professors generally have five to seven years to gain tenure. During this time, other faculty members study the person's work. If tenure is denied, then the assistant professor usually has a year to find another job.

An assistant professor who receives tenure becomes an associate professor. An associate professor may later be appointed a full professor.

Assistant, associate and full professors at American universities perform many duties. They teach classes. They advise students. And they carry out research that is published. They also serve on university committees and take part in other activities.

Other faculty members at American universities are not expected to do all those jobs. They are not on a tenure track. Instead, they might be in adjunct or visiting positions. A visiting professor has a job at one school but works at another for a period of time. An adjunct professor is also a limited or part-time position, to do research or teach classes. Adjunct professors have a doctorate.

Another position is that of lecturer. Lecturers teach classes, but they may or may not have a doctorate.

If you have a general question about the American education system, send it to special@voanews.com. And if you would like to find the other reports in our Foreign Student Series, go to WWW.51VOA.COM.

This VOA Special English Education Report was written by Nancy Steinbach. I'm Gwen Outen.