reduce by half

例句：

1. 1.The population of the city has been reduced by half in the past decade.
   过去十年里，该市的人口减少了一半。
2. 2.The cost of living has been reduced by 30% due to the government's policies.
   由于政府的政策，生活成本已经降低了30%。
3. 3. The company plans to reduce its carbon footprint by using more renewable energy sources.
   该公司计划通过使用更多的可再生能源来减少其碳足迹。