commercial rock gas的用法和樣例：
例句
- Natural gas is often present in the reservoir rock.
儲油岩中常有天然氣。 - Siberia is a major gas produced area.
西伯利亞地區是俄羅斯主要的天然氣產區。 - Petroleum gas can be used as fuel as well as a chemical material.
石油氣既可以用作燃料又可以用作化工原料。 - The phenomenon of vapor explosions threatens the safe storage and transportation of liquefied petroleum gas.
液化石油氣蒸汽爆炸是對其安全儲運構成很大威脅的一種觀象。
