Quatenary carbon atom
[医] 第四碳原子, 季碳原子
🧩 词语组成解析
🗣️ 情景例句
He likes that.
他喜欢那样。
A standard one. Replacement during the first year if all rules for proper use have been followed.
有一个原则，如果在一年内符合各种使用规定，就可更换。
and then there are three thousand million other Milky Ways, or galaxies, in the universe.
况且在宇宙中还有30亿个天河，即银河系。