ammonia is composed of nitrogen and hydrogen

例句：

1. 1. Ammonia is a colorless gas that canbe used as a fertilizer.
   氨是一种无色气体，可以用作肥料。
2. 2.The chemical reaction between ammonia andwater produces ammonia gas.
   氨和水之间的化学反应产生氨气。
3. 3. The factoryuses ammonia to produce fertilizers for the crops.
   该工厂使用氨生产农作物的肥料。