The Cultural Revolution brought China's education system to a virtual halt for a long time. In the early months of the Cultural Revolution, schools and universities were closed. Primary and middle schools later gradually reopened, but all colleges and universities were closed until 1970, and most universities did not reopen until 1972. The university entrance exams were cancelled after 1966, to be replaced later by a system whereby students were recommended by factories, villages and military units, and entrance exams were not restored until 1977 under Deng Xiaoping. Values taught in traditional education were abandoned. During the Cultural Revolution, basic education was emphasized and rapidly expanded. While the years of schooling were reduced and education standard fell, the proportion of Chinese children who had completed primary education increased from less than half before the Cultural Revolution to almost all after the Cultural Revolution, and those who completed junior middle school rose from 15% to over two-third. The educational opportunities for rural children expanded considerably, while those of the children of the urban elite became restricted by the anti-elitist policies.