sulfur cycle

例句：

1. 1. The sulfur cycle is crucial for the Earth's climate system.
   硫循环对地球的气候系统至关重要。
2. 2.Scientists are studying the sulfur cycle to better understand its impact on the environment.
   科学家正在研究硫循环，以更好地了解其对环境的影响。
3. 3.The sulfur cycle plays a vital role in the carbon cycle, as it helps to convert carbon dioxide into organic matter.
   硫循环在碳循环中起着重要作用，因为它帮助将二氧化碳转化为有机物质。