Isotopes
n. 核素；同位素（isotope的复数）
🗣️ 情景例句
They'll just make him sad.
那些只会让他悲伤。
Love lives in cottages as well as in courts.
爱情无贵贱，贫负皆有之。
Then they had a second child-a son. How happy they were!
后来他们有了第2个孩子一个儿子。他们多么高兴啊！