Inthepast,mandidnothavetothinkabouttheprotectionofhisen...
問題詳情：Inthepast,mandidnothavetothinkabouttheprotectionofhisenvironment.Therewerenotmanypeopleonearth,andnaturalresources（資源）seemedtobeunlimited（無限的）.Today,thingsaredifferent.Theworldhasbecometoocro...