R Christianson - 《Wood & Wood Products》 被引量: 0发表: 2014年 Problem Solvers: Problem--Counting Is for the Birds and Solutions--Multiplication along the Silk Road. Connecting mathematical thinking to the natural world can be as simple as looking up to the sky. Volunteer bird watchers arou...
The Road Not Taken ——Robert Frost 未选择的路 ——罗伯特·弗罗斯特 Two roads diverged in a yellow wood, 黄色的树林里分出两条路 And sorry I could not travel both 可惜我不能同时去涉足 And be one traveler, long I stood 我在那路口久久伫立 And looked ...