ureal

例句：

1. 1. Urea is a commonfertilizer used in agriculture.
   尿素是一种常见的农业肥料。
2. 2. The farmer applied the urea to the soil to enrich it.
   农民将尿素施于土壤中以增加其肥力。
3. 3. Urea is also used asa source of energy for some plants.
   尿素也被用作某些植物的能量来源。