Polymethylene
n. [化]聚亚甲基
🗣️ 情景例句
Haven't you finished balancing that checkbook?
你还没有核对完支票簿帐目吗？
He is a promising young man.
他是个有出息的年轻人。[分词作定语]
Twenty people had already left.
有20个人已经离去。