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山东省2014模拟》a
完形填空（共30小题；满分40分。a篇每小题1分，满分10分；b篇每小题1.5分，满分30分。）
阅读下面短文，掌握其大意，然后从11—20各题所给的a、b、c和d项中，选出最佳选项。
many of the world's pollution problems have been caused by the crowding of large groups of people into the cities．supply for the needs of the people leads to further 11 by industry．if the rapid increase of world popul
