B-b fraction
[化] 丁烷-丁烯馏分
🧩 词语组成解析
🗣️ 情景例句
I must say the products in Shanghai have improved very much in the past ten years.
我得承认上海的产品这十年来进步了很多。
I have a dog, but it's very quiet.
我有一只狗，不过它很安静。
Here's a pen.
这里有笔。