Polybromination
多溴化反应
🗣️ 情景例句
What are your favorite subjects?
喜欢哪些课程？
No one can call back yesterday.
往日不复返。
I went on an excursion recently, but my trip took me longer than I expected.
最近我作了一次短途旅行，但这次旅行所花费的时间比我预计的要长。