improved land

例句：

1. 1. The government has beenworking on improving the quality of the landfor years.
   政府多年来一直在努力提高土地的质量。
2. 2. The farmers have been using improved fertilizers to improve the productivity oftheir land.
   农民们一直在使用改良过的肥料来提高他们土地的生产力。
3. 3. Thenew irrigation system has significantly improvedthe quality of the land in the region.
   新的灌溉系统已经显著提高了该地区土地的质量。