1.粗鲁的___________ 2.行为，举止____________3.重要性_____________ 4.沙子_______
5.上升 ___________ 6.虽然 ___________ 7.法律 ___________ 8.水龙头_________
9.时期____________10.污染_____________ 11.回收，再循环 ___________ 12.逃跑_________ 13.oxygen_________14.level_____________15.garbage__________16.carbon dioxide_________ 17.sandstorm _________18.ozone layer________ 19.carbon ________ 20. desert__________
21. Mars__________ 22.radiation _________ 23. 灭绝___________
24.在地球上，到底 ______________25.温室效应____________________
