１９世纪末 ,２０世纪初美国经历了托拉斯垄断组织迅猛发展的阶段。小型企业纷纷合并成较大规模的企业。在缺乏法律约束的情况下 ,大型企业间利用签订协议来限制供应和抬高价格。他们往往通过降低价格、甚至不惜亏本来达到将弱小企业从市场排挤出去的目的 ,直至它们破产。竞争 At the end of the 19th century and the beginning of the 20th century, the United States experienced a period of rapid development of the monopoly of trusts. Small businesses have merged into larger companies. In the absence of legal constraints, large firms use agreements to limit supply and raise prices. They often achieve their own goal of marginalizing small and medium-sized enterprises from the market by lowering their prices, even at a loss, until they go bankrupt. competition