enechema

例句：

1. 1.The scientist discovered a new element in the laboratory.
   科学家在实验室发现了一种新的元素。
2. 2. The chemical reaction between hydrogen and oxygen produces water.
   氢和氧之间的化学反应产生水。
3. 3. The chemical agent used to clean the room is harmful to the environment.
   用来清洁房间的化学试剂对环境有害。