1972年2月21日，中共中央主席毛泽东在北京中南海会见到访的美国总统理查.尼克松。尼克松访华期间，中美双方在上海发表《联合公报》，两国关系在长达20余年的紧张之后开始走向正常化。（杜修贤 摄）

    The CPC Central Committee Chairman Mao Zedong meets in Beijing, the visiting U.S.president Richard Nixon February 21, 1972. During Nixon’s visit, the two sides in Shanghai issued a joint communiqué, marking a start of normalization on bilateral relations of the two countries in more than 20 years.（Photo by Du Xiuxian）