metallurgical coal的用法和樣例：
例句
- The necessity of expanded coal rank for CWM production and saving coking coal resources were discussed in this paper.
摘要闡述了節約煉焦煤資源，擴大制備水煤漿煤種范圍的必要性。 - Instead of pussyfooting around with coking coal, the west may one day address the most egregious imbalance of all.
與其在煉焦煤?jiǎn)?wèn)題上糾纏，西方有朝一日也許會(huì )針對一切失衡中最大的失衡。
