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1001 Edition: Constitutions
On October 1st, 1949 a grand ceremony was held in Beijing to mark the founding of the People's Republic of China. Although ...
科普中国 on MSN21 小时
不能久坐，我站着还不行么？
在办公室或教室坐一整天，难免浑身僵硬，肩颈腰背酸痛。即使下班或下课后拼命运动，也很难抵消久坐带来的不舒服。