撑: Ⅰ动词1.(抵住; 托住) prop up; support 短语和例子撑住屋顶 prop up a roof; 两手撑着下巴 hold one's chin in one's hands; 四根柱子撑着顶篷。 four pillars support the ceiling.2.(用篙使船行进) push or move with a pole 短语和例子撑船 pole
乙烯: [化学] ethylene; ethene; [有机化学] olefiant gas 短语和例子聚乙烯 polyethylene; polythene
