Cosanic acids
[化] 二十级酸; 二十级烷酸; 念酸(由C20到C29的廿酸)
🧩 词语组成解析
n. 酸, 酸类；有酸味的东西（acid的复数）
🗣️ 情景例句
Your grandfather went to the Engineering School there.
你爷爷进那个工学院。
Please sign a copy of our Sales Contract No.156 enclosed here in duplicate and return to us for our file.
请会签第156号销售合同一式两份中的一份，将它寄回我方存档。
It was beginning to get dark. I think we'd best stay the night here, I said.
天开始变黑。“我看我们最好在这里过夜，”我说，