To end a year of astonishing change, China has announced it will launch that most cherished of modern-day reforms, the carefree four-day weekend, as part of a festival full of tributes to the American way of life.

Sunday is the first day of Spring Festival, or the lunar New Year, and Peking's official media have dropped past reforences to a "revolutionary festival" -- meaning working through the holiday. Now it is everyone's revolutionary duty to have a ball, four days running.

American movies, including a science fiction thriller, are opening. Television stations plan holiday specials, highlighted by coverage of Vice Premier Teng Hsiao-ping's visit to Washington and gala entertainment at the Kennedy Center.

Former Chinese businessmen and industrialists, those symbois of the capitalist world who have suffered years of persecution, are being given back their high salaries, bank deposits and private houses, the official Chinese news agency said today. A Shanghai newspaper has gone Madison Avenue with a published code to advertising, largely forvidden in China until now. Advertising, it claims, will "make our cities beautiful, lift our spirits and make us feel pround of a thriving socialist economy."

Someone high in the Peking government, most likely the vice premier who will arrive in Washington as the festival gets under way, has decided what the limping Chinese economy needs is a good vaction.

"Every working man and woman in the cities will have a four-day vacation," the New China News Agency reported from Shanghal. "This is a real family holiday with reunions and lots of visits.

"People spend the festival with their families and will have a good rest before plunging into work for modernization," the agency reported from Peking.

For peasants, the Communist Party leadership of Shensi Province has decreed that male peasants "have a oneweek holiday.... Fenale peasants can have a two-week holiday." Those who have to work "must be awarded a bonus."

Lunar New Year for centuries has been a time of great feasting in China. But in the last few years of the life of Chairman Mao Tse-tung, conspicuous consumption and gay celebration were regularly discouraged in the press.

Since Mao's death in 1976, the new and more pragmatic leadership in Peking has experimented with more festive celebrations at New Year. It seems prepared this year to let out all the stops.

"It is estimated that up to the end of the holiday period on Feb. 16, the number of holiday passengers (on the nation's railroads) will be well over 100 million," the Chinese news agency said. Among the travelers will be a foold of relatives coming in to visit from Hong Kong and Macao, an estimated 25 percent increses over the number last year.

"An American science fiction film, 'Futureworld,' Charlie Chaplin's 'Modern Times' and the U.S. documentaries 'End of The Game' 'Undercurrent' as well as the British documentary 'Between the Tides' will begin showing at Spring Festival," the news agency reported from Peking. The "Hunchback of Notre Dame," with Gina Lollobrigida in low-cut blouses and Anthony Quinn in the title role, opened earlier this month in Peking.

A number of new Chinese movies also will be released, including an operatic version of 'Hsiang-Lin's Wife," a powerful ahort stroy by the premier Chinese writer of this century, Lu Hsun. It is a shattering tale of poverty and superstition ruining the life of a peasant woman in pre-Mao days, sure to make theater goers feel better about the few additional comforts they have in what is still a very poor country.

The official Chinese press says that many people will have more money to spend this year, as raises have gone to many workers and a bonus system has been revived. But the Chinese agency made a point of referring to still unattained luxuries to work hard for "Dangling from the balconies of apartment buildings are fish, meats and other perishables, for refrigerators are still beyond the reach of the majority of the people," the agency reported from Shanghai.

The Shanghai newspaper Wen Hui Pao suggested in an unusual Jan. 14 article just reaching here that healthy consumerism could be accelerated with "advertisements... in simple and clear language. Spelled out in vivid, graphic terms, they pack great drawing power."

Advertising has been denounced in the past as a capitalist business, the article said. But intermissions used to break up Chinese television programs are "a great waste of television time," it added.

"Foreign countries' television time between 7 and 9 p.m. is a 'golden period' with the largest audience. Advertising during this period produces the greatest results and is very expensive. One minute can cost several hundred thousand U.S. dollars," the newspaper said.

Of course Chinese advertising would not work this way, it added, but Chinese television stations should accept some foreign advertising "on a selective basis... This can both widen the horizon of the masses and add to our sources of foreign exchange."

In the same way, Chinese Politburo member Ulanfu announced, resuming apyment of high salaries to talented former industrialists who have been denied high wages for 12 years can encourage them to help in developing a modern economy.