今天投资于负责任林业的每一美元,明天都会成长为一百美元的环境和经济价值。
I think that the thing that makes mathematics worthwhile is the fact that it has this incredible structure that you can explore and discover.
每个家庭都是一个团结的小社会,自由和相互之间的感情是他们唯一的纽带。