w men jiao xiadediqiu shiyikéyán shi xing qiu tāde biao mian fu 我们脚下的地球是一颗岩石星球，它的表面覆 gāi zhe gé zhöng gé yāng de yán shi yóu de yán shi shi hei sede you de yán 盖着各种（试读）...