China yesterday unveiled parts of a new national constitution that appears designed to bring a permanent end to years of lawlessness and bureaucratic arrogance.

Yeh Chien-ying, 80, the Communist Party vice chairman and second-ranking leader in the country, read excerpts of the revised constitution to the fifth National People's Congress, China's parliament.

The New China News Agency released only a summary of the speech and no text of the new document, leaving the actual language of many of the key revisions to the 1975 constitution in doubt.

But the new constitution, among other things, restores criminal prosecutors and encourages citizen complaints.

The summary made clear that China plans a return to the stricter and more carefully supervised criminal procedures of the 1950s, and also indicated a desire on the part of top party leaders to persuade usually cautious Chinese to blow the whistle on corrupt and inefficient officials.

In perhaps the most important organizational revision, the new constitution restores the network of prosecutor offices "in view of the extreme importance of fighting against violations of the law and discipline," Yeh said. The offices were abolished in the 1975 constitution after they had tried to punish Red Guards and others involved in the factional fighting during the Cultural Revolution of the late 1960s. Chairman Mao Tse-tung argued that the disruptive "class struggle" was healthy, but those party officials most committed to this idea were purged one month after Mao's death in September 1976.

Yeh indicated that the new constitution would include, for the first time, Mao's call to "let a hundred flowers bloom, let a hundred schools of thought contend," the slogan of a brief period of intellectual freedom cut short in 1957 when Marxist doctrine came under attack. The post-Mao leaders, including Yeh, Party Chairman Hua Kuo-feng and Vice Chairman Teng Hsiao-ping, have revived the phrase in hopes of stimulating scientific thinking and technological progress that will save a faltering national economy.

They also appear to be convinced that more outspoken criticism of official actions, such as that found in the now prominent letters column of the official people's Daily, can help them govern. Their frustration at the inefficiencies and arrogance displayed by local leaders after 30 years of party rule seemed to pervade Yeh's speech.

Yeh said the new constitution "makes fairly big changes in the articles concerning organs of state and state personnel and sets strict and necessary demands on them, "according to the Chinese news agency account. "The most essential of these is to maintain contact with the masses. . . . It is necessary to have complete faith in them, respect their sense of responsibility to the revolution, care for and protect their socialist enthusiasm and initiative, share their feelings and sentiments and earnestly heed their criticism and complaints, particularly their criticism of leading bodies and leading cadres."

"All well-meant criticism from the grass roots and masses should be warmly encouraged The people's right to expose the evil-doers and evid deeds in state organs should be fully guaranteed," the news agency summary of Yeh's speech said.

The summary said nothing about restoring the presidency, or chairmanship of the People's Republic, an office foreign observers had speculated might be revived and given to Hua, Yeh, or Teng. The congress deliberations have yet to reveal the new government appointments that will signal the extent of Teng's growing influence.

Teng himself has received relatively little official press attention so far, while Hua has dominated the limelight. A New China News Agency dispatch yesterday spoke of congress delegates "choked with emotion" when Hua dropped in on some discussion groups.

The text of the new constitution is expected to be released after the congress adopts it, which is a foregone conclusion. A plenary session of the party Central Committee has already approved the document, endorsing the decision of the ruling party Politburo.

Yeh, who also serves as defense minister, said the new constitution would give unprecented attention to the need to "strengthen the revolutionalization and modernization" of the army. Chinese general have complained that the 3.5 million-member armed forces have been weakened by neglect of training during the years of political turmoil and also need new weapons.

A separate article of the constitution will be "devoted to our work in science and technology, underscoring the importance of vigorously stepping up our scientific and technological work," Yeh said.

The Chinese newspaper and television converage of the congress has focused to an unusual degree on the atmosphere of gaiety and good times. Old friends have exchanged personal news and conducted song and poetry fests.

That festive air continued yesterday, with the unexpected opening of two of Peking's most beautiful and centrally located parks for the first time in seven years. About 50,000 people crowded into Beihai (North Sea) and Chingshan (Coal Hill) parks before the end of the day, officials said, after early passerby found the gates opened and spread the word.

An official announcement vaguely blamed the 1971 park closings on the since-purged "Gang of Four" -- party dogmatists, who objected to frivolous entertainment.