This is the VOA Special English Education Report.

Graduate students often work as teaching assistants while they study in the United States. Teaching assistants may get money or get to take classes for free, or both.

A T.A. usually works about twenty hours each week. In some cases, the professors they assist have big undergraduate classes with hundreds of students. The professor gives one or two lectures a week, and teaching assistants lead smaller discussions at other times.

They also give tests, grade work, provide laboratory assistance and meet with students who need help. And they have their own educations to think about.

Labor unions have been working to organize teaching assistants who feel overworked and underpaid. Some schools have had strikes.

Another issue is the language barrier. Many states have proposed to require that teaching assistants be able to speak English well enough for students to understand them. Universities have increased their efforts to deal with this problem.

Our example school this week is the University of Southern California, in Los Angeles. The Institute of International Education says more foreign students go to USC than any other American university.

The American Language Institute at USC provides training to help international teaching assistants improve their English. The university requires most non-native English speakers to pass a test before they can become a T.A.

Those who went to college in an English-speaking country do not have to take the test. The same is true for those who scored at least twenty-seven on the speaking part of the TOEFL Internet-based test.

The exam at USC is a fifteen-minute spoken test that involves two examiners. Students talk about their education and interest in the school. Then they present some issue or idea from their area of study, and answer questions about it from the examiners.

Those who do not score high enough on the test have to take classes to improve their English. Until their English is better, some departments give them jobs that do not require them to communicate with students.

And that's the VOA Special English Education Report, written by Nancy Steinbach. Listen next week for the next part in our Foreign Student Series on higher education in the United States.

MP3 files and transcripts of the series are at WWW.51VOA.COM. If you have a question or comment, write to special@voanews.com, and be sure to include your name and country. I'm Bob Doughty.