中华人民共和国建国已50年，在这50年中，我国发生了天翻地覆的伟大变化，科技事业也与其它行业一样，取得了巨大的进步。总体看来，我国科技事业在50年的发展中，可以说是道路曲折，成绩斐然，已经确立了面向21世纪的稳固的发展基础。在建国初期，为了国家的安全，我国优先发 The founding of the People's Republic of China has been 50 years. During these 50 years, great changes have taken place in our country. As in other industries, science and technology have made tremendous progress. Overall, China's science and technology undertaking, over the past 50 years, can be described as a twists and turns with outstanding achievements. It has established a solid foundation for development in the 21st century. In the early days of the founding of New China, for the sake of national security, our country was given the priority