Polymethylene derivatives
[建] 聚甲烯衍生物
🧩 词语组成解析
n. [化]聚亚甲基
派生物
🗣️ 情景例句
What is your responsibility there?
你在那主管什么？
Wade not in unknown water.
不知水的深浅，不可粗心趟水过河。
Once the oxygen content of the air had risen to 25% it was ready to burn.
一旦氧气在空气中的含量达到25%，它就要燃烧。