一、数字类 (一)“第一”类 1．世界上第一个把圆周率的数值准确推算到小数点以后第七位数字的杰出数学家:祖冲之。 2．我国现存第一部完整的农业科学著作:《齐民要术》。 3．“天下第一关”:山海关。 First, the number of categories (a) “first” category 1. The world’s first mathematician to accurately predict the value of the pi to the seventh digit after the decimal point: Zu Chongzhi. 2. China’s first complete agricultural scientific book: “Qi Min Yao Shu.” 3. “The first pass in the world”: Shanhaiguan.