垄断市场

例句：

1. 1.The company's monopoly over the market has been challenged by a new competitor.
   该公司对市场的垄断地位受到了新竞争者的挑战。
2. 2.The government is trying to break up the monopoly and open up more competition in the industry.
   政府正试图打破垄断，增加该行业的市场竞争。
3. 3. Monopolies are often seen as a threat to consumer choice and freedom of information.
   垄断常常被视为消费者选择和信息自由的威胁。