In Pristina, capital of the autonomous Yugoslav province of Kosovo, young people customarily stroll up and down the main street, or ''corso,'' in the evening.
Young women walk arm in arm, eyeing the young men. Clusters of teen-agers and university students chat on street corners or shout greetings to one another.
As if symbolizing the divisions of this troubled province, the ethnic Albanians walk on one side of the street and Serbs on the other.
This is Kosovo, poorest of Yugoslavia's six republics and two autonomous provinces, where the ethnic Albanian majority erupted into violent demonstrations in March 1981. By the time the protests were put down, nine people were dead, 250 injured, and more than 1,000 imprisoned. Yugoslavs were stunned into recognizing a serious national problem.
Although a surface calm has returned to Pristina, a ripple of tension runs underneath.
The armed police and Army presence here would be unusual elsewhere in Yugoslavia. Officers walk in pairs, guns slung over their shoulders and walkie-talkies clipped to their belts. And there is a fear here, particularly among young people, of the security services.
''If I tell you something,'' an Albanian student said to a visiting reporter, looking over his shoulder, ''and it is 'wrong,' I can go to jail.'' Albanians, he said, are the ''Negroes'' of Yugoslavia, long discriminated against. There are 1.3 million ethnic Albanians in Kosovo, that equals half the population in Albania itself.
Since the riots, federal and regional authorities have used a mixture of economic carrots and political sticks to keep the province in line. There was a general effort to rechannel development funds to more productive projects than the prestige construction sites that formerly received aid.
In an attempt to keep Kosovo's economy moving forward, even though investment is being slashed elsewhere in the country, aid to Kosovo is to be maintained at current high levels, with adjustments for inflation and devaluations of the dinar.
Even so, there were several bomb explosions in Pristina this fall. When a transformer blew in the region's electric power plant, rumors of sabotage cropped up.
Officials in Belgrade, the Yugoslav capital, are unsure how best to address the tangle of ethnic, social, and economic frictions that have poisoned relations between Kosovo's Albanian majority and the region's Serbs, who are a minority in this province although they are the largest ethnic group in Yugoslavia as a whole.
At first Belgrade emphasized the province's economy; now it is also concentrating on its young people. Kosovo has Europe's highest birthrate at 2.6 percent, and Yugoslav authorities see the youth population as a breeding ground for Albanian irredentism. The 1981 riots began in the Pristina university's dining hall as a protest against poor living conditions but quickly took on nationalist overtones.
''The younger generation has been indoctrinated,'' said Zoran Miskovic, secretary of the Chamber of Republics and Provinces in the Yugoslav Parliament. Parliament has reviewed legislation to restructure the curriculum at the university and increase the number of students earning technical, as opposed to liberal arts, degrees.
''They should learn the languages of the other Yugoslav nationalities,'' Mr. Miskovic added. ''Then they would circulate more on a voluntary basis.''
But recent conversations with university students in Pristina revealed a considerable gap between government reform efforts and the students' perception of what is going on in the province. When a visitor pointed out to students the large share of development funds donated by the wealthier republics, more than one laughed in disbelief.
''Where is it going to? Where are the factories? Show me,'' an engineering student challenged.
Students' faith in the regional development effort was not strengthened by the disclosure this fall of a series of local financial scandals, including imprisonment of five officials in the major import-export company. Their skepticism is deepened by official pressure on university faculty and students to ''unmask the enemy,'' as a local Albanian Communist Party official put it, and to inform on anyone using nationalist slogans.
Hard living conditions for students and Yugoslavia's bleak outlook for the economy and employment concern government officials trying to smooth over the ill-will between Serbs and Albanians.
Students at Pristina's university, Yugo-slavia's only Albanian-language university, sleep three and four to a dormitory room. Often they lack textbooks. The ultramodern library lacks books in Albanian. After last year's riots, the import of Albanian-language books from Albania was stopped.
Kosovo has Yugoslavia's highest unemployment rate - there are 32 job-seekers for every vacancy. Yugoslavia's nationalities policy allows each ethnic group in this linguistically and culturally diverse country to be educated in its own language, but that leads to problems for Albanians seeking work in the more developed republics.
''You do not know how difficult it is to get a job here,'' a student said. ''There are no jobs. If I go to another republic, like Croatia, they will give a job to a Croatian before they give it to me. The Albanian is last.''
Provincial officials are hoping their development drive will create 58,000 new jobs by 1985. But there are 400,000 students in the area's schools, and 40, 000 in the university.
As an Albanian journalist put it, ''Before, there were uneducated people who couldn't find jobs. Now there are educated people who can't find jobs.''