People used to think environment protection was secondary to economic development. In order to develop agriculture and industry, many tropical forests were cut down to make room for farm lands, and supreme grasslands were damaged in search for mines. Water and air pollution has transformed the earth dramatically. Nowhere in the world is exempt from its impact. Faced with all these, people have finally realized the importance of sustainable development, which means striking a balance between economic development and environment protections.
人们曾经认为和发展经济相比，环境保护是次要的。为了发展工业和农业，大片的森林被砍伐，来腾出空地作农田。为了开矿，优良的草场遭到破坏。而水和大气污染则使整个地球的面貌发生了巨大的改变。世界上没有一个角落能够幸免。面对这一切，人们终于认识到可持续发展的重要性，即经济发展和环境保护必须保持平衡。