1. Sulphur dioxide is a pollutant and a major contributor to acid rain. 二氧化硫是一种污染物,并且是形成酸雨的主要因素。
2. They reported that clouds are an important and heretofore uninvestigated contributor to the climate. 他们报告说,云是影响气候的一个重要因素,但迄今尚未进行过调查研究。
3. What was a significant contributor to the past glory of public schools? 是什么对公立学校过去的辉煌做出了贡献?
4. Sulfur dioxide, a major contributor to acid rain, is an especially serious pollutant because it diminishes the respiratory system's ability to deal with all other pollutants. 二氧化硫是酸雨的主要成因之一,它是一种特别严重的污染物,因为它会降低呼吸系统处理其他污染物的能力。
5. Every contributor has worth (20:05). 每一个贡献者都是有价值的(20:05)。