数学是一门活生生的学科,随着新的思想和发现不断演变。
父子之间要亲爱,君臣之间要有礼义,夫妇之间要挚爱但还要有内外之别,老少之间有尊卑之序,朋友之间要有诚信之德。
Climate change isn’t a distant problem—it’s here, and forests are our first line of defense.
"The best stories are those that refuse to be finished."